PackFitter
Packing Calculator & Fit Tool
Plan. Pack. Fly.
Last updated: April 2026
Bag volume alone doesn't determine if your bag fits. Carry-on acceptance depends on external dimensions, airline policy, weight limits, and sometimes your booking type. This page covers the rules that matter and links to airline-specific fit pages for every bag size.
A bag that fits on Southwest might not fit on Ryanair. Airlines differ on four things that determine whether your bag boards with you: carry-on dimensions, personal item rules, weight limits, and booking-based restrictions. Some airlines include overhead bin access in every booking; others charge extra for it or restrict carry-ons to priority boarding.
Each airline below links to bag-specific fit pages that answer one question: will this bag actually fit on this airline? Every page includes a calculator that checks your exact packing setup against that airline's published limits.
| Airline | Carry-on limit | Weight |
|---|---|---|
| Delta Air Lines | 22 × 14 × 9 in | No limit |
| United Airlines | 22 × 14 × 9 in | No limit |
| American Airlines | 22 × 14 × 9 in | No limit |
| Southwest Airlines | 24 × 16 × 10 in | No limit |
| Ryanair | 21.7 × 15.7 × 7.9 in | 10 kg (22 lbs) |
| EasyJet | 22 × 17.7 × 9.8 in | 15 kg (33 lbs) |
Major U.S. airlines typically do not publish or enforce standard carry-on weight limits on most domestic routes. European budget airlines are more likely to enforce both dimensions and weight, including at the gate.
On U.S. carriers, most fares include both a personal item and an overhead bin carry-on at no extra charge. On European budget airlines, the overhead bin is often a paid add-on — your included cabin bag may only be a small under-seat personal item. This means a 25L bag can go either way: it fits under most seats, but on budget airlines it may be the only bag you're allowed without paying extra.
The distinction matters because a bag that technically fits the carry-on sizer doesn't help if your booking doesn't include overhead access. Check both dimensions and your booking details before you fly.
Pick your airline from the cards above, then choose the bag size closest to yours. Each airline page includes a calculator that lets you set your exact trip length, climate, packing style, and extras like a laptop or extra shoes. It'll tell you how much of the bag your setup uses and whether it fits that airline's carry-on limits.
If you're not sure what bag size you need yet, start with a packing guide for your trip length — then come back here to check airline fit.
Packing guides by trip length →
Carry-on bag sizes guide (25L–45L) →
Popular airline pages
Will a 35L backpack fit on Delta? →
Will a 25L backpack fit on Ryanair? →
Carry-on dimensions are based on published airline policies as of early 2026. Airlines update their policies periodically — always verify with your airline's website before traveling. Weight limits listed are for the carry-on bag only and may not include personal items.
The fit calculator on each airline page uses real bag measurements, a 15% dead-space factor, and airline-specific dimension limits. Packed external dimensions determine final fit — not the bag's liter rating. Final acceptance depends on gate agent discretion.
This page is based on aggregated airline policies, real-world packing constraints, and typical travel scenarios.
This content reflects real-world packing scenarios and typical airline policies. Airline enforcement may vary based on aircraft, route, and boarding conditions.