How to pick bikepacking bags without making the noob mistake everyone makes

Picture this. You scroll Instagram, see a perfectly photographed Apidura setup, decide yes, that's me now, and buy a 16L seat pack, a 14L bar pack, and a 5L frame bag — before you've packed a single sock. Three weeks later, on day one of your trip, the sleeping bag won't fit in the seat pack, the bar pack swallows nothing but tortillas, and your rain jacket is bungeed to your handlebars like a 1990s hostage.

You're not alone. I've watched friends do this. I've done this. The bag industry's marketing has a name for you: customer.

The order matters

The right order is boring:

Decide what you're taking.
Add it up. Volume in litres.
Then pick bags.

Most people reverse this. They buy bags first because bags are sexy — they have logos and reviews and YouTubers using them. Gear is the boring part: a tent that lives in your basement, base layers you've owned for three years, the same stove you bought on a whim. Bags get the dopamine; gear gets the chores.

But the bags have to carry the gear. Not the other way around.

The 2-litre buffer

Most useful number you'll read all week: add 2 litres to whatever you calculated.

Why?

You will buy a snack at a gas station and need somewhere to put it.
It will rain, and the rain jacket you wore yesterday is now a wet ball that needs its own container.
Cool sticker from a brewery? It's on your phone case now, fine. But the second layer you didn't think you'd need at 3am? That goes in a bag.
Compression is theoretical. Real-world packed volume is 10–15% bigger than the spec sheet, because you don't have the patience to roll your sleeping bag the way the manufacturer's marketing team does.

If your gear adds up to 18 litres, get bags that total at least 20. If the math says 25, plan for 27–28. Trust me. Or trust everyone who's ever had to bungee a windbreaker onto an aerobar at a roadside.

"But I might need it"

There's a parallel mistake on the gear side: the "I might need it" pile. The third headlamp, the second multi-tool, the extra cookpot for the dinner you'll never actually cook.

Useful trick: pack the night before, then unpack everything and ask each item, did I use this last trip? If no, it stays home. Apply ruthlessly. You'll be amazed how much volume you free up — and then you don't even need that 28L setup.

Mix brands. It's fine.

This one's quick: people get superstitious about matching brands. "I have Apidura up front so I need Apidura on the back." No you don't. Bags don't care about each other. Buy whatever fits your bike, your gear, and your budget, in that order. The bikepacking police are not going to revoke your card if your handlebar roll is Restrap and your seat pack is Ortlieb.

Where this site comes in

This is roughly why I built Veloadout — to make step 1 and 2 take five minutes instead of an evening with a notebook. Add the gear you own, see the total volume, see what bag sizes fit. Optionally pick the actual bag models if you want the affiliate links to buy me a coffee.

Then buy bags. Then go ride.