You can bring liquids on a plane in containers of 3.4 ounces (100 milliliters) or less each. All these containers must fit within one clear, quart-sized (about 32 ounces) zip-top bag per passenger. This is known as the TSA's 3-1-1 liquids rule: 3.4 ounces per container, 1 quart-sized bag, 1 bag per passenger

. In terms of total liquid volume, you can carry approximately 25 to 27 ounces of liquids if you fill the quart-sized bag with multiple 3.4-ounce containers, but the exact amount depends on how many containers fit in the bag

. Exceptions to this rule include medically necessary liquids, baby formula, breast milk, and duty-free liquids purchased after security, which can exceed 3.4 ounces but must be declared and handled separately at security

. Liquids over 3.4 ounces must be packed in checked baggage, where there is no TSA liquid limit, though airline weight limits and packaging precautions apply