Volume unit reference table
Exact milliliter equivalents for every unit supported by this converter.
| Unit | Symbol | Milliliters equivalent |
|---|---|---|
| Milliliter | mL | 1 mL |
| Liter | L | 1,000 mL |
| Cubic meter | m³ | 1,000,000 mL |
| US gallon | gal (US) | 3,785.411784 mL |
| UK (imperial) gallon | gal (UK) | 4,546.09 mL |
| US cup | cup | 236.5882365 mL |
| US fluid ounce | fl oz (US) | 29.5735295625 mL |
- The US and UK gallon are two independently defined units, not a rounding of the same value — a UK gallon is about 20% larger than a US gallon.
- This converter uses the US fluid ounce (29.5735295625 mL) and US cup (236.5882365 mL); it does not include the UK/imperial fluid ounce (≈28.41 mL) or the Australian/NZ metric cup (250 mL).
- Cubic meters are a large unit for everyday liquids — 1 m³ equals 1,000 liters, easy to mis-key by a factor of ten.
How are volume units defined?
The liter is a non-SI unit accepted for use with the SI, defined as exactly one cubic decimeter (0.001 m³). The US liquid gallon is defined as exactly 231 cubic inches, which — using the exact inch-to-metric conversion — equals exactly 3.785411784 liters. The UK (imperial) gallon is defined separately, as exactly 4.54609 liters under UK legislation. Because the two gallons come from independent historical definitions, they differ by about 20%: a UK gallon holds roughly 1.2 US gallons, a frequent source of error when comparing fuel economy, fuel prices or recipe volumes across US and UK/Commonwealth sources.
This converter's cup and fluid ounce are the US legal definitions used in US cooking and nutrition labeling: the US cup is exactly 1⁄16 of a US gallon (236.5882365 mL), and the US fluid ounce is exactly 1⁄128 of a US gallon (29.5735295625 mL). These differ from the UK/imperial fluid ounce (≈28.41 mL) and from the metric cup (exactly 250 mL) used in Australian and New Zealand recipes, neither of which this converter includes.
How to use this volume converter
- Enter the volume value you want to convert.
- Select the unit that value is currently in — milliliters, liters, cubic meters, US or UK gallons, US cups, or US fluid ounces.
- Read the converted results across the other six units, shown at once.
- When comparing a US-sourced volume with a UK/Commonwealth-sourced one, double-check whether "gallon" or "fluid ounce" refers to the US or UK definition — they are not interchangeable.
The formula behind volume conversion
Every input value is first converted to milliliters using its exact factor, then re-expressed in each other unit by dividing by that unit's own milliliters-equivalent. All figures below are exact legal or defined values, not rounded approximations.
Common mistakes
- US vs UK gallon — the imperial (UK) gallon is about 20% larger than the US gallon (4.546 L vs 3.785 L), so applying one figure where the other is meant misstates fuel volumes, fuel economy and recipe scaling.
- Confusing the US fluid ounce (29.57 mL) with the UK/imperial fluid ounce (≈28.41 mL) — this converter uses US definitions throughout.
- Treating a metric "cup" (250 mL, common in Australian/NZ recipes) as interchangeable with the US legal cup (236.59 mL) this converter provides — a meaningful difference in baking.
- Dropping a factor of 1,000 between liters and cubic meters, or between milliliters and liters, when converting large or small volumes.
अक्सर पूछे जाने वाले सवाल
Is a US gallon the same as a UK gallon?
No. A US (liquid) gallon is exactly 3.785411784 liters, while a UK (imperial) gallon is exactly 4.54609 liters — about 20% larger. The two units were defined independently by US and UK legislation, so a US recipe, fuel-economy figure or container size cannot be compared directly to a UK one without converting.
How many milliliters are in a US cup?
One US cup equals exactly 236.5882365 milliliters, defined as exactly 1⁄16 of a US gallon. This is the standard cup measure used in US recipes and nutrition labeling, and differs from the 250 mL metric cup used in Australian and New Zealand recipes.
How many fluid ounces are in a US gallon?
There are exactly 128 US fluid ounces in a US gallon, since the US fluid ounce is defined as exactly 1⁄128 of a US gallon (29.5735295625 mL). This is also why there are exactly 16 US cups in a US gallon (8 fl oz per cup).
Why is the imperial gallon bigger than the US gallon?
The two units come from separate historical definitions rather than a shared origin. The UK imperial gallon was legally fixed at exactly 4.54609 liters, while the US gallon derives from an older English wine gallon standard fixed at exactly 231 cubic inches (3.785411784 liters) — a smaller historical reference volume that the US retained after UK measures were reformed in the 19th century.
How many liters are in a cubic meter?
Exactly 1,000 liters, since the liter is defined as exactly one cubic decimeter (0.001 m³) and a cubic meter contains 1,000 cubic decimeters. This makes cubic meters a convenient unit for large volumes such as water tanks, shipping containers or concrete pours.
संदर्भ
- National Institute of Standards and Technology (NIST). Special Publication 811: Guide for the Use of the International System of Units (SI), 2008 Edition.
- United Kingdom. Weights and Measures Act 1985, Schedule 1 — definition of the imperial gallon as exactly 4.54609 liters.
- NIST Handbook 44, Appendix C: General Tables of Units of Measurement (US gallon, cup and fluid ounce definitions).
- International Bureau of Weights and Measures (BIPM). The International System of Units (SI Brochure), 9th edition, 2019 — the liter as a non-SI unit accepted for use with SI.