Volume Converter

The cooking-and-tanks family

Volume brings together the unit family a kitchen, a garage and an aquarium shop actually argue in: millilitres, litres, cubic metres, teaspoons, tablespoons, US cups and US gallons. This page converts across all seven, with the cup and the gallon pinned to US customary sizes — a US cup is 236.5882365 millilitres and a US gallon is 3.785411784 litres, definitions the panel states below the result so no reader inherits a metric-cup assumption.

The anchors worth carrying: 1 litre is 4.226753 cups or 0.264172 gal; 1 cup is 16 tablespoons or 48 teaspoons exactly; 1 gallon is 4 quarts, 16 cups — a quart never appears as its own unit here, so hop to gallons or cups first if a recipe speaks in quarts.

A worked example, step by step

Problem two ways: a stock pot recipe from a US blog says 10.5 cups of stock, sold in your shop only in 1-litre cartons; and a 60-litre aquarium must be dosed by a product labelled in gallons.

1. Stock: 2.5 litres × 4.226753 = 10.566882 cups. The recipe's "10.5 cups" is a hair short — buy three 1-litre cartons and hold the third in reserve.
2. Reverse check: one carton is 1 l = 4.226753 cups; multiplying back metres the recipe's estimate, so no arithmetic was lost.
3. Tank: 60 l ÷ 3.785411784 = 15.850323 gal. A label saying "dose 1 oz per 5 gal" needs the gallon figure, not the litre one.
4. Half-litre bottle: 0.5 l = 2.113376 cups — the figure that turns "drink 8 cups a day" advice into "about four 500 ml bottles".
5. Small spoons for a syrup: 1 tbsp is 14.786765 ml and 1 tsp is 4.928922 ml, so 3 tsp = 1 tbsp exactly.

Every line is one division or multiplication against the anchor constants, and the tool's six-decimal output lets you decide the rounding: 15.850323 gallons reads as "about 15.85 gal" on a dosing card, while 10.566882 cups reads as "10.57 cups" on a card.

Anchor values, all in one row

The cup column is the fastest read for kitchen arithmetic: spoons are fractions of a cup (a tablespoon is exactly one-sixteenth of the US cup), and the litre-and-gallon rows are the hose-and-carton view of the same day. One cup is 48 teaspoons and 16 tablespoons exactly; the decimals elsewhere all stem from the definitions that 1 inch = 2.54 cm anchors at the bottom of the chain.

Where cups lie to you

The US cup (236.59 ml) is not the metric cup (250 ml) used in Australia and much of recipe-writing south of the equator, and it is not the imperial cup (284 ml) of older British cookbooks. Baking is the discipline where the difference matters — 6% to 20% flour-error lands in the crumb, not the wash-up. Volume for dry goods is doubly rough: a "cup" of brown sugar pressed firmly is not a cup of the same sugar spooned lightly, which is why professional baking weighs. Convert what must be converted precisely, and weigh what the outcome actually depends on.

Mistakes that quietly overflow the pot

• Assuming cup = 250 ml. That is a metric cup; US recipes under it by 13.4 ml per cup, and a six-cup batter drinks 80 ml of error.
• Serving imperial gallons to US labels. The imperial gallon is 4.546 litres, a 20% bigger drum — aquariums and fuel cans still get caught by this.
• Using a tbsp measure calibrated to a metric cup. Mismatched sets scale the whole recipe; keep each recipe inside one system.
• Reading m³ as a kitchen unit. 1 m³ is 1,000 litres — pool volumes live there; kettles do not.
• Dosing in teaspoons against a dropper's millilitres. 1 tsp is 4.929 ml, but infant doses use device-specific measures; match the label's unit.

Keep exploring

• Length Converter — the linear units underneath every volume definition.
• Area Converter — squares before cubes: m², hectares and acres.
• Data Storage Converter — capacity of a different kind: bytes across two ladders.
• Guide: Unit Conversion Mistakes to Avoid.