Jul 28, 2026

How to Choose Between a 30L and 40L Backpack: Which Size Is Right for You?

How to Choose Between a 30L and 40L Backpack: Which Size Is Right for You?

Choosing the right backpack size can make the difference between travelling comfortably and constantly wishing you had packed differently. Two of the most popular options are 30-litre (30L) and 40-litre (40L) backpacks. While they may seem similar, those extra 10 litres can have a significant impact on what you can carry, how you travel, and whether your bag suits your lifestyle.

So, should you choose a 30L or a 40L backpack? This guide breaks down the differences to help you make the right decision.

Understanding Backpack Capacity

Backpack capacity is measured in litres, which indicates the total volume available inside the bag.

30L Backpack: Compact, lightweight, and ideal for everyday use or short trips.
40L Backpack: Larger and more versatile, designed for extended travel or carrying extra gear.

The right choice depends on how you use your backpack rather than simply how much it can hold.

When a 30L Backpack Is the Better Choice

A 30L backpack is an excellent option if you prefer travelling light and only carry the essentials.

Perfect for:

Daily commuting
Office work
University or college
Day trips
Weekend breaks
Short business trips

Typical Items That Fit

A well-organised 30L backpack can comfortably hold:

15–17" laptop
Charger and accessories
Tablet
Notebook
Water bottle
Lunch
Headphones
Light jacket
One or two changes of clothes
Toiletries

If you pack efficiently, a 30L backpack is often all you need for a two- or three-day trip.

Advantages

Lighter to carry
Easier to organise
Fits comfortably under many airline seats
More convenient for public transport
Ideal for everyday use

Potential Drawbacks

Space can become limited if you're carrying:

Winter clothing
Camera equipment
Gym gear
Shoes
Bulky electronics

When a 40L Backpack Makes More Sense

If you travel frequently or need to carry more than just your daily essentials, a 40L backpack offers far greater flexibility.

Ideal For

Business travel
Week-long holidays
Digital nomads
Remote workers
International travel
Carry-on luggage (depending on airline size restrictions)

What Can Fit Inside?

A quality 40L backpack can typically hold:

Laptop
Tablet
Chargers
Four to seven days of clothing
Toiletries
Shoes
Travel documents
Camera equipment
Water bottle
Jacket
Snacks and accessories

Many travellers find they can replace a small suitcase entirely with a well-designed 40L backpack.

Advantages

Excellent packing capacity
Great for longer trips
More versatile
Can replace checked luggage for many journeys
Better suited to mixed work and leisure travel

Potential Drawbacks

Slightly heavier when fully packed
Can encourage overpacking
May feel bulky for everyday commuting
Some airlines have stricter cabin baggage size limits, so always check before you fly

Comparing 30L vs 40L

Feature	30L Backpack	40L Backpack
Everyday commuting	⭐⭐⭐⭐⭐	⭐⭐⭐
Office use	⭐⭐⭐⭐⭐	⭐⭐⭐⭐
Weekend trips	⭐⭐⭐⭐	⭐⭐⭐⭐⭐
Business travel	⭐⭐⭐⭐	⭐⭐⭐⭐⭐
International travel	⭐⭐⭐	⭐⭐⭐⭐⭐
Carry-on flexibility	⭐⭐⭐⭐	⭐⭐⭐⭐*
Comfort when full	⭐⭐⭐⭐⭐	⭐⭐⭐⭐
Packing capacity	⭐⭐⭐	⭐⭐⭐⭐⭐

*Cabin baggage allowances vary between airlines.

Consider Your Travel Style

Before choosing a size, ask yourself a few simple questions.

How long are your typical trips?

If most of your travel lasts one to three days, a 30L backpack will usually be sufficient.

If you regularly travel for four days or more, a 40L backpack offers valuable extra space.

Do You Carry a Laptop Every Day?

Office workers often need to carry:

Laptop
Charger
Documents
Lunch
Water bottle
Headphones

A 30L backpack is usually more than adequate for this type of daily routine.

Do You Want One Bag for Everything?

Many people prefer owning one backpack that works for commuting, business travel, holidays, and weekends away.

In this case, a 40L backpack often provides greater long-term value because it adapts to more situations.

The Role of Compression Technology

One of the biggest developments in modern travel backpacks is compression technology.

Compression systems allow you to reduce the volume of clothing after packing, creating significantly more usable space without increasing the bag's external dimensions.

This means a 40L backpack can often carry the equivalent of much larger luggage while remaining compact enough for comfortable travel.

For professionals, frequent flyers, and minimalist travellers, compression technology helps reduce the need for multiple bags.

Don't Forget Comfort

Capacity isn't everything.

A backpack should also include features such as:

Padded shoulder straps
Breathable back panel
Adjustable chest strap
Ergonomic design
Water-resistant materials
Quality zips
Multiple organisation pockets
Dedicated laptop compartment

These features become increasingly important as the amount of weight you carry increases.

Which Backpack Should You Choose?

Choose a 30L backpack if you:

Commute to work every day
Take short weekend breaks
Prefer travelling light
Want a compact everyday bag
Rarely carry bulky items

Choose a 40L backpack if you:

Travel regularly for work
Want one backpack for commuting and holidays
Need extra clothing or equipment
Prefer avoiding checked luggage whenever possible
Like having additional packing flexibility

Final Thoughts

There isn't a universally "better" backpack size—only the one that's right for your lifestyle.

A 30L backpack is an excellent everyday companion for commuters, students, and light travellers who value portability and simplicity.

A 40L backpack offers the flexibility to handle business trips, longer holidays, and everything in between, making it a smart investment for people who want one bag that can do it all.

Before buying, think about how often you travel, what you carry each day, and whether you need a backpack that can adapt to different situations. Choosing the right size now will make every commute, flight, and adventure more comfortable and organised.