What can I carry on a plane?

The carry-on rule checker that starts with the answer

Every traveler has stood in a security line wondering if the bottle, battery, or tool in their bag is about to be confiscated. The official sources have the answers — the TSA’s alphabetical table, CATSA’s lookup, scattered airline policy pages — but they are slow, jargon-heavy, and scattered across a dozen websites. Can I Carry It exists to close that gap: search an item, get a plain-English verdict in one glance, then drill into quantities, exceptions, and sources only if you need them.

How to check an item

1. Type the item in the search box above — vape, power bank, toothpaste, anything.
2. Read the short answer first: yes, no, or restricted, for both carry-on and checked bags.
3. Check the condition chips for exact limits — 3.4 oz bottles, 100 Wh batteries, blade lengths.
4. Switch between TSA (United States) and CATSA (Canada) with the region tabs where rules differ.
5. Flying with an infant, medication, or duty-free purchases? Look for the exception callouts.
6. Flying United Basic, Frontier, or Flair? Cross-check your bag size on the airline pages.

The four rules that decide almost everything

Most confiscations trace back to four patterns. First, the 3-1-1 liquids rule: containers of 3.4 oz (100 ml) or less, in one quart-size bag, per passenger — and it is the printed container size that counts, not how much is left inside. Second, lithium batteries: anything with a rechargeable battery that is not installed in a device — power banks, spare cells, vapes — must fly in the cabin, never in checked luggage. Third, sharp objects: if a blade can come out or exceed small-scissor limits, it belongs in the hold. Fourth, your airline’s contract: security may allow your bag while your fare does not, especially on Basic Economy and ultra-low-cost carriers where only an under-seat personal item is free.

TSA vs CATSA: nearly twins, with traps

The US and Canadian systems mirror each other — 100 ml liquids, one lighter, batteries in the cabin — but they are not identical. Canada’s scissor limit is 6 cm from the pivot, noticeably stricter than the TSA’s 4 inches. The American powders rule (containers over 12 oz screened separately) has no Canadian twin. Our region tabs surface these differences item by item instead of burying them in footnotes.

The exceptions that save trips

Three exemptions quietly override the rules travelers stress about most, and all three are surfaced as callouts on the item pages where they apply. Medically necessary liquids — insulin, injectables like Zepbound, cough medicine, contact solution in reasonable quantity — may exceed 3.4 oz when you declare them at the checkpoint. Baby food and breast milk are exempt from liquid limits when you travel with an infant. And duty-free purchases ride through connecting security in the sealed tamper-evident bag with the receipt inside. Knowing these three turns "throw it away" moments into non-events.

Cheap fares, expensive bags

The costliest misunderstanding in air travel is assuming that because security allows your bag, your ticket does too. United’s domestic Basic Economy, Frontier, Allegiant, Air Canada Basic on North America routes, Canada’s Flair and WestJet UltraBasic all include only a small under-seat personal item — the overhead-bin bag costs extra, and gate prices are punishing. That is why every airline page on this site leads with what your fare actually includes, not just dimensions, and why the comparison table marks carry-on fees before size. Measure once, check your fare class, and the surprise fees disappear.

Why every answer here is dated

Baggage rules change quietly: fare families shift, battery guidance updates, scanner technology relaxes old limits at some airports. That is why each page on this site shows a visible “Last verified” date with links to the official sources we checked, and why we would rather mark an item “unverified — confirm with your airline” than guess. Accuracy beats completeness, every time. Found something outdated? The contact page reaches a human.