Travel day bag

Your travel day bag is your constant companion, whether you’re moving between destinations or going out for your daily activities. Imagine yourself boarding a plane, standing in a crowded metro (subway) or walking a thronged street. Think about the activities you’ll do at your destinations: exploring a city on foot, plunging into markets, hiking the hills behind the town, going out to night spots and more. 

With rare exceptions, your day bag will be with you the entire time. So it better be the right bag for your needs.

A day bag for traveling should not be too big: it has to carry only what you really need and no more. We humbly suggest that you should limit yourself to 15 liters, while experienced travelers manage with 9 – 11 and fanatical minimalists can manage 7 liters. If you’re carrying 20 – 30 liters its because you have loads of camera gear, a portable office, bulky outer garments or recreational equipment.

Your day bag must be comfortable all day long. It has to provide defenses against pickpockets and bag slashers as well as rain and dirt. And, hey, it’s great if it looks good too.

You have two basic choices, a backpack or a courier bag. Sling bags, floppy messenger bags, totes, fanny packs etc. are all inappropriate for travel.

Don’t scrimp on quality features to save a small amount of money.

Day bag uses

Your day bag is your constant companion, serving two distinct functions.

In-transit

You need to keep your valuables with you when you’re on a plane, train, bus or other form of transport, in stations and airports and on the street. If they’re not, you risk loss or theft. Keep them close in your day bag.

Your main bag might be in an overhead bin or rack, down in the bus cargo bay or checked-in for a flight, so you can’t leave any valuables in it. They have to be in your day bag, along with all the other stuff you need while moving from place to place (tickets, schedules, phone, reading material, water, tissue, ear plugs, sunglasses…).

Never keep your passport, money and important documents in your day bag — they belong in your travel wallet (a money belt, hidden pocket or other stash).

Daily excursions 

Some travelers insist that a day bag is not needed when wandering a city. That may be true in limited situations, but most of the time you’ll want to carry at least some stuff that won’t fit in your pockets: a light jacket, water, umbrella, sunglasses, sunscreen, notepad and pen, map, phone and maybe a camera and other items.

Unlike the in-transit use, you won’t be carrying all your valuables on daily excursions — some will stay in your room. This not only reduces your load, but limits your losses if your bag goes missing.

The best travel day bag designs

There are two basic travel day bag designs, based on how they’re carried: backpacks and shoulder bags. Travel versions of each differ from non-travel types.

Travel day backpack

A backpack is the classic day bag for travelers. While they are the most versatile, they’re not ideal for all situations.

There are several variants of backpack:

• Conventional — Recommended. If you’re going for a backpack, this is what you want. Size varies, but there are two padded shoulder straps, a main pouch that may or may not have further pouches and sleeves inside, and at least one external sleeve or pouch. They’re made of tough nylon to withstand wear and tear. Some better and bigger ones come with a waist strap, to stabilize the bag. (An unpadded strap is not built to take weight off your shoulders.) To reduce sweating, better ones also have a panel and/or mesh system to separate the pack from your back.
• Packable — Not recommended. These are simply thin ripstop nylon sacks with unpadded shoulder straps. Their supposed virtue is that they can be packed into themselves to form a pouch the size of your fist, so they’re ideal if you have to put everything in to your main bag. Compact yes. Practical no. Because it has no suspension or anti-sweat systems, this is not the bag you want to carry around all day, every day. You could use one for shopping or laundry.
  • The only time you’ll need to pack your day bag and its contents in your main bag is when taking a budget airline that allows just one bag for carry-on. Even if you can get everything into your main bag, it won’t be a common use compared to your other in-transit and daily excursion use.
  • For in-transit or daily excursion use, packables fail tests of durability, carry-comfort, protection of contents from impact and security from pickpockets.
• Main bag with attached backpack — Not recommended. Some clever manufacturers sell a combination main backpack with an attached conventional day pack. It looks like an elegant, color-coordinated solution — but it’s not. The idea is that you don’t have to look like a dork by hanging your day pack off your front, while carrying the main backpack on your back. Ironically, you’re better off looking like a dork.
  • The attached day pack extends your center of gravity further away from your body, so the weight distribution is harder on your shoulders than if you hang a backpack off your front. It won’t matter for a short walk, but you’ll feel the strain during a Long March.
  • Hanging a backpack off your front is also far more secure than leaving it out of sight back there where the pickpockets and bag slashers can play.
  • You have to take the entire main backpack off to get at anything in the day pack. Super-inconvenient if all you want is a sip of water.
  • Manufacturers charge a premium for all this cleverness.

All our comments from here on will be about conventional backpacks, unless otherwise noted.

Travel shoulder bag

Normally, shoulder bags hang to one side, but can be easily held in front or swung behind. The shoulder strap must be long enough to be worn cross-body, since hanging the bag off one shoulder is not secure.

Shoulder bags for travel come in several types — courier bags, messenger bags, totes etc. — but labeling by manufacturers is not consistent. What one manufacturer calls a “messenger,” another will call a “courier.” We’ll use our own nomenclature!

• Courier bag — Recommended. These are taller than they are wide and usually come with a flap over the front. They have a bit of structure and stiffness, so they hold their shape. Small is beautiful: 7 – 14 liters is the best range, although some go up to 20 liters.
• Messenger bag — Not recommended. Messenger bags are wider than they are tall and feature a large flap over the front. They are unstructured and floppy because they are intended to form to your body when on a bicycle. We don’t like them because they get in the way (especially if you have a backpack on) and can be sweaty.
• Totes, purses and others — Not recommended. These are large, flattish bags that are often carried by the hand grips or off one shoulder. Fashion almost always trumps function. They are clearly not suitable for travel.

Go for the “courier bag” design only.

Unsuitable types of day bag

• Sling bag — The sling bag has a pea pod shape with small to medium volume. Normally worn cross-body, it goes over one shoulder and can be worn front or back. It doesn’t look quite as silly as a backpack when worn on your front. For numerous reasons, the sling bag can’t compete with either a backpack or a courier bag.
• Fanny packs, phone holsters & other abominations — Just. Don’t. Apart from looking totally stupid, pickpockets and bag slashers know exactly where to go.

Which day bag design will work for you?

Think carefully before you choose, as there are consequences that you’ll have to live with every day of your trip. (See below for a detailed discussion of each quality feature.)

• Versatility — What situations are well managed by the design and where does it fail?
• Carry-on — If you plan to travel with carry-on bags only (no checked luggage), what combination of main bag and day bag will work best?
• Capacity — Can the bag carry all your stuff, both in-transit and on day excursions?
• Packing efficiency — Are the pockets and sleeves helpful for finding what you need, when you need it?
• Access — Can you get in to the bag without shifting it or taking it off?
• Carry comfort — Is the bag comfortable to carry for hours when fully loaded?
• Security & protection — How well will your bag secure your stuff from pickpockets and bag slashers? Will it protect against rain, dust and other depredations?
• Appearance — Does it matter to you whether you look like a student or tourist, or do you want to look more cosmopolitan?
• Build quality — Will the bag last your whole trip without damage to zippers, seams and other parts?
• Value for money — Is a premium day bag worth the money or is something less costly perfectly fine?

✔︎ = Good     ~ = Okay      ✗  = Poor

How to choose the best travel day bag

Before you consider the quality features of a day bag for traveling, you need to choose the design you want:

• Most important use — Will you be moving a lot between destinations? Will you be doing many vigorous outdoor activities or will you spend most of your time on less energetic pursuits?
• How much stuff you need to carry — Will you have a lot of large and/or heavy valuables to protect while going from place to place? Do you need recreational gear or bulky extra garments on your day trips?
• Type of main bag — Day backpacks are not a great match with a main backpack, because two backpacks, one big and one small, are clumsy when moving from one destination to another. Courier bags are much better. Travel day backpacks are fine with a wheeled main bag.

Versatility

In-transit use of a day bag is mainly to protect your valuables while you’re on a plane, train, bus or other conveyance, as well as in airports, stations and on the street with all your stuff. Your valuables will have to share the space with other stuff. On a bus, for example, besides multiple electronic devices, you might have food, water, toiletries and perhaps a extra piece of clothing.

Using the bag for daily excursions can vary enormously. You could spend one day wandering the streets of a city and the next day climbing the mountain behind it. You could be at the beach during daylight hours, with just a tube of sunscreen. Then you’re out the same night at a club or concert.

A single day bag has to serve for all these purposes.

A backpack can go anywhere and leave your hands free. It’s ideal for hikes and other active outdoor pursuits where you may need extra clothing, gear, water or food. It’s also good for carrying your valuables in transit, but only if your main bag is not a backpack. The combination of main backpack and day backpack is clumsy at best.

While not ideal for a hike, a messenger bag can be pushed to the small of your back and serve adequately unless you need both hands unobstructed (for steep climbs or on bad footing perhaps). If you plan to do a lot of vigorous outdoor activities, a messenger bag may be both too small and in-the-way, compared to a backpack. Messenger bags are better for urban adventures. Either is good for the beach.

Recommended for versatility: backpack if you will do a lot of vigorous outdoor activities, otherwise a courier bag.

Carry-on (and carry-in)

Decision time: do you want to travel with carry-on baggage only or will you check-in your main bag on every flight? There are arguments for and against both options. If you plan to check-in your main bag on every flight, then the rest of this discussion doesn’t matter. If you’re taking few flights, maybe the cost won’t be too high. But, if you plan on more flights and want to go carry-on only (as most pro travelers do), your choice of day bag will be limited by size and design.

Most airlines classify day bags as a “personal item.” The size and weight limits for personal items are set by the airline itself, so they vary among airlines. Airlines — especially budget airlines — are getting more strict. A big day bag (such as a backpack of 20 liters or more) is likely to draw the attention of airline personnel and you could be forced to check-in your main bag at the gate, where the charge is often punitive.

Some budget carriers allow just one bag in the cabin of of the aircraft. If that one bag is your main bag, you’ll have to place your day bag and most of its contents inside it. And that main bag still has to be within modest carry-on limits. Getting your day bag and its contents inside may not be possible. If not, you’ll just have to pay to check your main bag and hope the low ticket price makes the baggage fee, security risk and hassle worth it.

If your messenger bag or backpack might be considered too large, wear it behind you as you bring your main bag by the handgrips or wheels through the gate and on to the aircraft. When the airline staff check you out from the front, it doesn’t look like too much. Note that, if your main bag is a backpack, it’s a bad idea to wear it on your back when boarding. Combined with a day bag in front, it will look bulky and you could be required to check in the main backpack.

Your best chance to get the maximum volume on to an aircraft as carry-on is a combination of travel backpack (36 – 45 liters) and courier bag (13 liters or less). The same hide-the-bag principle applies to get your day bag into museums and shops that normally require you to check-in your bag: courier bags are less of a threat than backpacks.

Recommended for carry-on: courier bag.

Capacity

Apart from the design type of your day bag, this is the hardest question to answer. Day backpacks range from 10 – 30 liters, while courier bags range from 4 – 20 liters.

Many travelers assume that there’s no harm in going a bit big, just in case. But this assumption is incorrect. Big bags invite over-packing, get in the way as you move and are often flagged for check-in by airlines, museums and stores. You want the smallest bag that will do the two jobs (in-transit and daily excursion).

As with your main bag, ask yourself what you truly need to carry. Then reduce it. Experienced travelers manage with 7 – 14 liters. Larger bags are justified only for those who plan in advance to carry bigger loads of camera equipment, mobile offices, cold weather clothing or recreational equipment.

Here’s a sample pair of lists for one traveler (your lists may differ).

The in-transit list has a few large and heavy valuables that you don’t have to take with you on daily excursions, while the daily excursion list has lots of small items. Either way, you can get all this stuff in a small day bag. How to Travel managed these lists (minus the guide book and with a non-bulky extra garment) using an 11 liter courier bag, with room to spare.

Recommended for capacity: either courier bag or backpack, but keep it under 15 liters.

Packing efficiency

Unlike your main bag, which is essentially a box to move your stuff from place to place, your day bag needs some organization into pockets and sleeves so that you can find items when you need them. You don’t want to waste time at the front of a ticket window lineup, fishing in the depths of your bag for a pen that you know is in there… somewhere. Organization also helps keep your most valuable stuff safer. That said, manufacturers tend to “over-engineer” day bags.

External

Many bags have too many external pockets and sleeves. You can’t put anything valuable in them and each one is a soft target for thieves. 

You need just one external zippered sleeve or pocket to have quick access to commonly used items, such as tickets, a bus schedule, a map or sunglasses. Even though you would not carry valuables in this pocket, the zipper should provide some deterrence to pickpockets.

An elastic pocket for a water bottle is also very handy.

Internal

Sensible internal organization helps you quickly find what you need most often. But even here, there are too many options. Who uses the key fob almost all day bags have? Marketing departments love to provide photos, showing you where your passport and credit cards can go — but you won’t be keeping them there because they’ll be in your travel wallet or hidden pocket.

Besides the main compartment, many bags have a padded laptop sleeve. This is fine if you’re one of the minority of travelers who need to carry a laptop. The laptop sleeve should not have it’s own external zippered access — yet another thief magnet in need of a lock. Still other bags, especially the smaller ones, have a tablet sleeve. If you don’t plan to carry a laptop or tablet, you don’t need to give away precious volume in a small day bag.

Some bags have a sizable unpadded interior pocket that could accommodate a tablet, phone and/or camera. (Any devices kept here should have their own padded sleeve or case for impact and scratch protection.) The pocket should not hang all the way to the bottom of the bag, where a bag slasher could still get to it.

A second, small interior sleeve is good for small stuff that’s not needed constantly, but would be hard to find rolling around the bottom of the main compartment. Here’s where you could put your sunscreen, insect repellant, lip balm, tissues and more.

Recommended for packing efficiency: either backpack or courier bag, but one with minimal external pockets and sensible internal ones.

Access

The whole idea of a day bag is that you will need at least some of the stuff that’s in it during the day or during your move between destinations. This is a small but important attribute.

• Backpack — If you’re wearing a backpack, you have to take it off to get to anything in it. Even if the backpack has an external pocket for your water bottle, you can’t get to it without taking the pack off. In addition, taking the backpack off and putting it down constitutes a security risk.
• Courier bag — If you’re using a courier bag, it’s right there and you can easily get stuff out and put stuff in. And you can leave it on while doing so, virtually eliminating security risk.

Recommended for access: courier bag.

Carry comfort

Since you’ll have your day bag with you constantly, carry comfort might soon seem like the most important attribute. You won’t be happy with your bag if your shoulders, back or neck get strained, a strap is chafing you or the bag is glued to you with sweat.

It bears repeating that the most important strategy to improve carry comfort is to carry less! After that, it depends on what you’re doing.

In-transit

Moving in-transit between destinations can range from easy to arduous. If you have wheeled luggage and can attach your day bag to the handle, you’re on easy street… unless the street isn’t easy. Then you’ll have to carry both your main and day bags over the cobblestones, up that hillside path, along the beach or up five flights of stairs. If your main bag and day bag are both backpacks, then the day backpack will either be attached to the back of the main pack or hanging back-to-front off your chest. The latter might make you look like a pregnant turtle, but at least the weight distribution will be better. A well-made courier bag can hang to the side or front and should be okay for limited walks, as long as it’s not too heavy.

Recommended for carry comfort: courier bag if your main bag is a backpack, otherwise either.

Daily excursions

Daily excursions are much easier. If it weren’t for the “two backpacks” problem when in-transit, a backpack would be your best comfort choice.

Backpacks

Backpacks are especially good for heavier loads because they distribute weight to both shoulders, stay relatively stable and are out of the way behind you, leaving you hands free. Day backpacks come with a wide variety of suspension systems, with larger packs usually having more.

• Shoulder straps — Better packs include padded shoulder straps, a sternum strap to hold the shoulder straps together. 
• Waist strap — This is not the padded, weight-bearing hip belt found on larger backpacks, but unpadded webbing used to stabilize the bag. Some larger packs have padded hip belts, but these come at a high cost in weight and volume.
• Ventilation panel and/or mesh — Backpacks are notorious for causing sweat if they lie against your back in warm weather or when you exert yourself. Some better quality day backpacks have mesh and/or panel systems to keep the backpack away from your body.

Courier bags

A courier bag, worn cross-body over one shoulder, will tend to move around, mostly from side to front. Over the course of a day, you will adjust the carry position frequently from front to side to back or vice versa. Depending upon weight and shoulder strap padding (or the lack of it) you may also switch shoulders as strain sets in. On the plus side, courier bags stay away from your body, so they don’t have the sweat problem of backpacks.

• Shape — Slim bags that are taller than they are wide will hang and stay put better than wider, thicker bags.
• Shoulder strap length — The range of shoulder strap length has to accommodate your body size when worn cross-body. Men with big shoulders and deep chests may find the strap on some bags too short.
• Shoulder strap padding — For all day use, a courier bag must have grippy and breathable padding where it rests on your shoulder. The padded part has to cover the entire area where your shoulder contacts the strap, plus a bit so that the seams don’t rub on you. The pad must adjust along the length of the strap to fit small or large people — a fixed pad may not adjust sufficiently when you move the bag to front or back. Padding is critical for carry comfort over long hours, so it’s shocking that some otherwise reputable manufacturers do not provide one on some models of courier bag. Fortunately, third party pads are available, as long as you’re okay with black.

Recommended for carry comfort: backpack.

Security

You will be out in the streets, on public transport, visiting attractions, sitting in restaurants and doing other things in public places. Pickpockets, slashers, snatchers and con men all inhabit these spaces, too, from the glittering cities of Europe to the sunny beaches of SE Asia. Can your choice of day bag contribute to protecting the contents? Oh, yes.

First, understand that thieves look for two things: valuables worth stealing and easy, low risk access to them. Tourists and travelers carrying day bags are assumed to have stuff worth stealing in them. And that assumption is correct much of the time. So how easy is it to steal these goodies? Partly, it’s your body language and how alert you seem. And partly, it’s what kind of defenses you have on both your clothing and your bags. If you appear alert and have even modest defenses, the thief will look for another target, someone less aware and less defended.

What kind of bag and how is it worn?

A backpack not only marks you as a tourist, but is vulnerable to pickpockets when worn on your back, because you cannot see what’s going on back there. If you’re squeezed like a sardine at a subway station or walking on a crowded street, you should keep your bag in front of you. But if that means wearing your backpack on your chest… well, that looks super bad, doesn’t it? Now you’re a goofy looking paranoid tourist with something worth protecting. Don’t hang your backpack off one shoulder either, especially where there’s motorcycle traffic, since motorcycles are the favored tool of bag snatchers.

Courier bags are much better. In a crowded environments, your courier must be worn cross-body — hanging it from one shoulder makes it vulnerable to bag snatchers. It can be positioned to your front, side or back, depending upon the situation you find yourself in. In a crowded street or on public transit, you can keep in front, with one hand on the bag. On a quiet street or mountain trail, you can push it behind you. 

Defensive features

• Minimum external pockets — More pockets means more options for a thief. Ideally, your day bag will have just two external pockets. It’s nice to have one flat pocket for tickets, maps, sunglasses and maybe a crushable hat. Don’t put anything valuable in this pocket. The second one that’s pretty handy is a side pocket for a water bottle.
• Cover or flap — A flap with clasp that covers the zippered access to the main compartment makes access for pickpockets a two-step process. That alone will send the thief to another victim, someone with just one step to the goodies.
• Zippers and secure clasps — An ordinary zipper is vulnerable to an accomplished pickpocket, so it’s good to have zippers that take one additional step to open, such as a clasp to the body of the bag. If the bag also has a flap, then the pickpocket now has three steps to access your stuff. If your bag’s zippers don’t have this extra clasp, you can hack it by linking the zipper pull to the body of the bag with a size “0” s-carabiner. Tiny padlocks are too much hassle to open and close all day, easy to misplace and signal that the contents of that pocket are valuable.
• Slash-resistant or slash-proof material — Heavier fabric will be harder for slashers to cut, compared to the thin nylon on “packable” backpacks and other cheap bags. Some manufacturers go one step further and offer material with metal webbing in the material, preventing the sharp blades of slashers from spilling the contents of your day bag into their hands.
• Hanging interior pocket — If your bag has an interior pocket that doesn’t extend near the bottom of the bag, you can put your most valuable items in it. If your bag is slashed, items in the main compartment may be lost, but not your high value possessions. It’s better still if the interior pocket is also zipped.
• RFID protection — Luggage marketers go nuts about protecting your debit and credit cards — even your passport — from signal theft by scoundrels with scanners. There’s not much evidence to support the threat of a RFID theft epidemic. But even if every café in Paris was crawling with crooks, you won’t be carrying these essentials in your day bag! So RFID protection might help for your travel wallet, but is not a necessary feature on your day bag.

Protection of contents from damage

As with your main bag, your day bag must protect its contents from rain, dust and the light impacts of daily use. Courier bags are more vulnerable to impact because they swing free, compared to a backpack held snug against your back. However, larger backpacks are often bumped against hard objects and people.

• Fabric — Rip-stop nylon is the minimum. Stiff, heavier fabrics are better. Bonded polyurethane on the inside will help repel moisture.
• Closure and zipper covers – Keeping the contents safe from light rain, dust and impact requires complete zipper closure of all external pockets and a rain flap to cover those zippers.
• Rain cover — Day bags don’t come with rain covers. If you’re going to a destination in the rainy season, you can get one made. Material and sewing is super cheap in middle and poor countries.

Recommended for security : courier bag.

Appearance

Your main bag should favor function over form and your day bag should also be intensely practical. After all, you’ll be carrying it with you all day every day. Don’t compromise too much function just because a bag looks cool.

Design

That said, you might give more consideration to the appearance of your day bag. Just as some technical clothing makes you look prepared for the jungle when you’re in the city, backpacks make you look like a student, hiker or bicycle commuter. If you’re okay with that, fine.

But, as with clothing, it’s better to look like everyone else on the street and sport an unburdened urban look. A small courier bag manages this well enough. Some of them are built purely for function, while others adopt a more fashionable appearance.

Again, if your main bag is a backpack, then a day backpack is a big no no. Attaching the smaller pack to the larger one is a bad idea (see above), but you can always make that compromise. But if you don’t… is there any traveler more dorky looking than one with a backpack on his back and another backpack hanging off his front?

For both backpacks and courier bags, avoid designs that appear hi-tech or look-at-me fashionable. These suggest to thieves that there might be valuable contents inside.

Keep in mind the strategy for boarding aircraft and taking your day bag into museums. A small shoulder bag is easier to get past the check-in counter.

Color

Some bags are lovely colors, but you don’t want the bag to stand out. A low key bag doesn’t draw as much attention.

Backpacks come in two styles: urban and recreational. Urban backpacks are used in the work environment and have a sleeker, understated look. Some recreational backpacks look similarly understated, but many of them look like athletic shoes, with bright colors, big logos, flashes, stripes… whatever makes them look-at-me gaudy. Functionality aside, you want the understated look.

Whether backpack or courier bag, you don’t want very dark or mid to light colors because they won’t hide the scuffs and dirt that are going to happen all the time. Also consider your clothing color scheme. How’s that orange bag going to look with your blue outfit? If you have a choice, go for a muted tone in a similar color range as your clothing.

Recommendation: muted courier bag, the smaller the better.

Build quality

Build quality features are much the same as for your main bag, although fabrics and fittings don’t have to be so heavy duty.

Fabric

Is the exterior fabric durable? It does not have to be as heavy as your main bag, since it will not receive such rough handling. Still, it has to be rugged enough to take bumps, scrapes and even slashing attempts by thieves. A good grade of ripstop nylon or polyester will do. It should be lined inside with polyurethane to block moisture.

Zippers

Are the exterior zippers rugged enough to bear the strain of constant use and tight packing?

• Coil type is okay — While we recommend chain type zippers on your main bag, coil will do fine for your day bag. Coils have finer teeth and are easier to open and close.
• Molded plastic — Molded plastic is better than metal. The teeth (“elements”) are molded directly on to the tape, making for a very strong zipper.
• YKK brand — There are many brands of good zippers, but you can’t go wrong with Japan’s famous “YKK” brand zippers. The letters “YKK” are stamped on the slider pull tabs of all YKK zippers.
• Zipper tape — The zipper tape should be sewn to the bag with at least a double set of stitches on each side. You’re going to open and close the zipper many times every day, so it needs to be well attached to the body of the bag.

Other hardware

Will the buckles, cinches and clasps survive heavy use and impacts?

• Buckles, strap adjusters and other hard parts — These should be made of tough material. Good quality metal is fine, but high grade plastics (Duraflex etc.) have a better strength to weight ratio. Beware of the cheap plastics on inexpensive bags — they’ll break just when you need them to perform.

Sewing

Good sewing is fundamental to durability and really differentiates quality day bags from cheap ones. Here are the details, but they’re hard to confirm, so your best bet is to buy a reputable brand.

• Thread — Is a quality thread sewn well enough to endure the stresses of constant handling and occasional overpacking? Grab where a strap joins the body of the bag and pull. The thread should not stretch. Strong nylon thread should be used. Some makers use UV-resistant thread that won’t deteriorate from extended exposure to sunlight as quickly as conventional threads.
• Stitch count — Stitching should be 2.4 – 4 stitches per cm (6 – 10 per inch). Any less is too weak, while any more will tend to separate the tightly woven fibers of the bag fabric too much.
• High tension points — Look for box-stitching or cross-stitching at high tension points, such as where shoulder straps and hand grips meet the body of the bag.
• Zipper tapes — Double stitching is good for all seams under stress, especially zipper tapes. 
• Finish — Seams in other wear areas should be lock-stitched to prevent any thread break from causing the entire seam to come unstitched. External seams should be sealed with waterproofing, although you can’t tell from visual inspection and manufacturers almost never mention it. Internal fabric edges should be finished to prevent them from fraying all the way back to the stitches. 

Recommended: either backpack or courier bag, but from a reputable brand with a guarantee.

Value for money

You will rely on your day bag for traveling every single day of your trip, so we strongly urge you to go for quality. That means prioritizing function over form, but not if it means the bag is 30 liters and lime green.

This isn’t as big a decision as your main bag, which can easily go north of USD 200. A good travel day bag can be bought for USD 50 – 70. (Choices outside the US are fewer and often more costly.) If it’s a difference of just USD 10 or 20, get the better bag.

Recommended: either courier bag or backpack, with strong feature set for the price.