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Volume Converter

Convert metric and imperial volume units. Supports liters, gallons, cups, milliliters, fluid ounces, tablespoons, teaspoons, and more. Includes a cooking mode with US, UK, and metric cup comparisons.

Quick Reference

1 cup = 16 tbsp = 48 tsp
1 cup = 8 fl oz = 237 mL
1 tbsp = 3 tsp ≈ 15 mL
1 fl oz ≈ 30 mL
1 L ≈ 1 qt (4 L ≈ 1 gal)
1 UK gal = 1.2 US gal
Quick:
⚠️ Regional Differences: Cup and tablespoon sizes vary by country. This mode shows comparisons between US, UK, Metric, and Australian measurements.
Options

How to Use This Converter

Use Single Conversion mode to convert one value between two units—pick your source and target, enter a number, and click Convert. The swap button between dropdowns reverses the conversion direction. Quick conversion buttons set common unit pairs with one click. Use Cooking Mode when following international recipes that use unfamiliar measurements.

Convert to All mode shows your value in every available unit at once, grouped by category—useful when comparing across measurement systems or when you're not sure which unit you need.

The options panel controls decimal precision, scientific notation for extreme values, and whether to display formulas and reverse conversions. For cooking, 2 decimal places is enough. Scientific work may need 6 or more.

Metric Volume Units

Metric volume measurement is built around the liter. One liter equals 1,000 milliliters, and each milliliter equals one cubic centimeter (or "cc" in medical shorthand). Because the system is base-10, converting between liters, milliliters, and microliters just means moving the decimal point. Deciliters (100 mL) and centiliters (10 mL) show up often in European recipes and beverage labels.

Metric units are used for science and shipping across most of the world, and most international recipes use milliliters and liters rather than cups.

US Liquid Measurements

In the US, liquid volume builds on the gallon, with each step down dividing by simple whole numbers. A gallon is 4 quarts, a quart is 2 pints, a pint is 2 cups, a cup is 8 fluid ounces. That makes a gallon 128 fluid ounces. Kitchen measurements add tablespoons (2 per fluid ounce) and teaspoons (3 per tablespoon) to the hierarchy. A cup holds 16 tablespoons or 48 teaspoons. You'll see these relationships all the time when scaling recipes or substituting measuring tools. The US dry pint and dry quart are different units used for dry goods like berries—a dry pint is around 551 mL versus the liquid pint's 473 mL.

UK and Imperial Volume Measurements

UK imperial gallons differ quite a bit from US gallons due to their original definitions. The imperial gallon was set to equal the volume of 10 pounds of water at a specific temperature, giving around 4.546 liters. The US gallon, based on an older English wine measure, holds only around 3.785 liters—making the UK gallon roughly 20% larger.

This 20% gap affects all related units. A UK pint contains 568 milliliters; a US pint holds 473 milliliters. British visitors ordering a pint of beer in America get less than they would at home.

UK fluid ounces are a bit smaller than US ones (28.41 mL vs 29.57 mL), but since a UK pint has 20 fluid ounces compared to 16 in a US pint, imperial pints still come out larger. The UK has mostly switched to metric, but imperial measures stick around in road signs and pub pours, plus older cookbooks.

US vs UK Cups and Tablespoons

Cup sizes vary a lot. A US customary cup measures 236.59 mL, while the US legal cup (on nutrition labels) rounds to 240 mL. Metric cups used in Australia, New Zealand, Canada, and increasingly in the UK equal 250 mL. The traditional UK imperial cup measures 284.13 mL, and Japanese recipes use a 200 mL cup. In baking, where precision matters, these differences can throw off results.

Tablespoons vary by region. The US tablespoon is about 14.79 mL (often rounded to 15 mL), matching the metric tablespoon. Australian tablespoons measure 20 mL—a full third larger. When using Australian recipes, their "1 tablespoon" means about 1⅓ US tablespoons. This changes the teaspoon relationship: most countries count 3 teaspoons per tablespoon, but Australia counts 4. Check where a recipe comes from—it affects your measurements.

Cooking Volume Conversions

Kitchen conversions mix accuracy with what's actually doable. For liquids like water, milk, and oil, volume measurements work well because density stays consistent. Dry ingredients like flour, sugar, and cocoa can pack differently depending on how you scoop them, making weight more reliable for serious baking. If a recipe gives weight, use weight. For volume measurements, these conversions help. Some equivalents are good to know: 1 cup = 16 tbsp = 48 tsp = 8 fl oz, 1 tbsp = 3 tsp, and 1 fl oz = 2 tbsp.

Scaling recipes up or down often creates awkward fractions. Halving 1/3 cup gives you "2 tablespoons plus 2 teaspoons"—technically right but tedious to measure. Some shortcuts help: 5 tablespoons plus 1 teaspoon equals 1/3 cup, 10 tablespoons plus 2 teaspoons equals 2/3 cup. When scaling creates impossible amounts like 1/8 teaspoon, a "pinch" works fine for home cooking.

Cubic Volume Units

Cubic measurements describe three-dimensional space rather than liquid capacity, but the two approaches connect mathematically. One cubic meter equals 1,000 liters, one cubic centimeter equals one milliliter, and one cubic foot holds about 7.48 US gallons. These conversions matter for construction, shipping, and engineering where you're measuring space rather than pouring liquids. Imperial cubic units follow length relationships: one cubic foot contains 1,728 cubic inches (12×12×12), and one cubic yard contains 27 cubic feet. Concrete, mulch, and gravel are sold by the cubic yard. Refrigerators specify capacity in cubic feet. Engine displacement used to be listed in cubic inches in America (a "302" engine meant 302 cubic inches), though modern specs use liters (that same engine shows as 5.0L now).

The Liter-Kilogram Connection

Water links metric volume and mass on purpose. At maximum density (around 4°C), one cubic centimeter of water weighs one gram. At larger scales, one liter (1,000 cubic centimeters) weighs one kilogram, and one cubic meter of water weighs one metric ton (1,000 kilograms)—so a full 200-liter water tank weighs 200 kilograms before counting the tank.

Oil Barrels and Industrial Volumes

The oil barrel (42 US gallons, about 159 liters) dates to Pennsylvania's early oil fields in the 1860s. Producers used whatever containers they could find—whiskey barrels, fish barrels. The 42-gallon size became standard because it matched common wooden barrels and stayed light enough for manual handling.

Other barrels exist at different volumes: US beer barrels hold 31 gallons, UK beer barrels around 43 gallons, wine barrels about 31.5 gallons. Hectoliters (100 liters) appear in brewing and agriculture.

Medical and Scientific Volumes

Labs and hospitals need accurate volume measurement, almost always in metric. Milliliters cover most lab needs; micropipettes measure microliters (μL) for small-scale tasks like PCR and cell culture. Nanoliters and picoliters are used in microfluidics and single-cell analysis. In medical contexts, "cc" (cubic centimeter) still appears as a synonym for milliliter, especially for injections and IV fluids, even though "mL" is now standard. Standard doses often reference 5 mL (one metric teaspoon)—that's why medicine cups mark that line. Blood donation takes around 470 mL (roughly one pint). IV bags come in 250 mL, 500 mL, and 1,000 mL sizes.

Practical Conversion Tips

A few memorized conversions cover most daily needs:

  • 1 liter ≈ 1 quart (so 4 liters ≈ 1 gallon)
  • 1 fluid ounce ≈ 30 mL (exact: 29.57)
  • 1 cup ≈ 237 mL (exact: 236.59)
  • 1 tablespoon ≈ 15 mL (exact: 14.79)
  • 1 teaspoon ≈ 5 mL (exact: 4.93)
  • 2 cups ≈ 500 mL (exact: 473)

Use exact factors for baking and lab work, or when measuring medication. For cleaning supplies or rough estimates, rounded numbers are fine. Temperature affects volume slightly; most specs assume room temperature.

Common Conversion Mistakes

Confusing US and UK gallons or pints creates issues. Fuel economy figures get hit hard by this—UK miles per gallon always looks higher than US mpg for the same car because UK gallons are bigger. When talking about beer internationally, specify which pint you mean. Recipe sharing across the Atlantic requires the same care.

Using the wrong regional cup size throws off recipes without warning. Two cups of flour means very different amounts with a 237 mL US cup versus a 250 mL metric cup or a 284 mL UK cup. Australian tablespoons confuse cooks with their 20 mL size instead of the expected 15 mL. Mixing up volume and weight is another issue—one cup of butter weighs differently than one cup of flour, even though both are "one cup." For baking, weight measurements fix this.