Carry-On Liquids Rules: Size Limit and Toiletry Checker

How to Use the Carry-On Liquids Checker

The checker sits under the heading "Check Your Toiletries." Each row has four fields: Item (text), Size (a number), Unit (oz or mL), and Type (Toiletry / other liquid, Medication, or Infant or child food / drink). The × button removes a row. The checker runs in your browser, and nothing you enter is sent anywhere.

The checker loads with four example rows: Shampoo at 3.4 oz, Toothpaste at 100 mL, Sunscreen at 6 oz, and Liquid medicine at 8 oz marked Medication. The quick-add chips (Shampoo, Conditioner, Toothpaste, Sunscreen, Face wash, Body lotion, Perfume, Hand sanitizer, Hair gel, and Dry shampoo (aerosol)) each add a row with a typical size already filled in. Edit that size to match the printed label on your container, because the limit applies to each container. "+ Add an item" adds an empty row.

Each row shows one of four verdicts. Quart bag and Checked bag verdicts also show the size converted to the other unit:

• "Quart bag": the size is 3.4 oz (100 mL) or less.
• "Checked bag": the size is over the limit.
• "Exempt": the Type is Medication or Infant or child food / drink.
• "Add a size": no size is entered.

How the Checker Applies the Carry-On Liquids Rules

An item entered in ounces passes at 3.4 or less. An item entered in milliliters passes at 100 or less. The checker converts between the units using 1 US fluid ounce = 29.57 mL, and it shows that converted figure next to each Quart bag or Checked bag verdict. TSA writes the limit as 3.4 ounces (100 milliliters), so the checker accepts those two numbers as written. For the rule itself, see the TSA travel liquid rules guide.

The conversion shows where the two limits differ. 3.4 oz is about 100.5 mL, so an item entered as 3.4 oz passes. An item entered as 101 mL (about 3.42 oz) does not. The four example rows give this worked example:

• Shampoo 3.4 oz → Quart bag (≈ 101 mL)
• Toothpaste 100 mL → Quart bag (≈ 3.38 oz)
• Sunscreen 6 oz → Checked bag (≈ 177 mL)
• Liquid medicine 8 oz marked Medication → Exempt

Exemptions for Medications and Infant and Child Food

Set Type to Medication or Infant or child food / drink, and the checker shows Exempt whatever the size. The verdict depends only on that Type setting, so the 8 oz medication in the example is not tested against the 3.4 oz limit. TSA's liquids page lists "Medications" and "Infant and child nourishments" among its exemptions. That page does not explain the screening steps for either group, so look up each item in TSA's What Can I Bring? tool before you fly.

The Exempt verdict answers only the size question. Items that alarm during screening get additional screening, according to the same TSA page. The summary counts exempt items apart from the quart bag and checked totals.

When the Answer Is Wrong for You

The checker follows TSA's rules for U.S. airport checkpoints. Airports outside the U.S. set their own liquid rules. A trip that starts at one of those airports follows that airport's or that country's rules, not these verdicts.

Duty-free bottles follow a separate path. On inbound international flights with a U.S. connection, duty-free liquids over 3.4 oz may be carried on only under TSA's conditions. TSA's conditions are that you bought them internationally within 48 hours, the retailer sealed them in a transparent tamper-evident bag with no sign of tampering, and you carry the original receipt. They are still screened, and TSA recommends checked baggage for them. Without that bag, they go in checked baggage. The checker has no duty-free option, so an over-limit bottle still shows Checked bag.

Two more limits sit outside the verdicts. TSA's toothpaste entry says the final decision rests with the TSA officer on whether an item is allowed through the checkpoint, so no verdict here overrides that officer. The checker also cannot tell whether all bag items physically fit in one quart-sized bag. You test that by packing the bag yourself.

Carry-On Liquids Rules for a Carry-On-Only Trip

When any item shows Checked bag, the checker shows a tip: flying carry-on only means each such item needs a container of 3.4 oz (100 mL) or less, or a checked bag. For each Checked bag item, pick one fix and run the check again. Buy a smaller container and enter its printed size, which should change the verdict to Quart bag. Or plan to move the item into checked baggage, where TSA says larger containers go.

For the quart bag itself, the liquids packing guide has packing tips. The carry-on packing list builds a full list for a carry-on-only trip, and the one-bag packing guide covers the rest of the bag. Work through these steps in order:

• Enter every toiletry, including the medication and infant or child items.
• Replace each chip's typical size with the printed size on the label.
• For each Checked bag item, swap to a container of 3.4 oz (100 mL) or less, or plan a checked bag.
• Click Copy result to copy the final list with its verdicts.
• Pack the quart-sized bag at home to confirm every container fits in it.

Frequently Asked Questions