Calculator
What the Cup Converter does
Cup Converter: 1 cup = 236.5882365 mL, so multiply a cup (US) value by 236.5882365 to get millilitre, or divide to go back. Example: 1 cup = 236.5882365 mL.
With Value, From and To entered, the Cup Converter works out Result, How it was calculated and Reverse conversion. Everything recomputes live, which makes it easy to test a few scenarios in a row.
Converting once from the original figure beats chaining approximations. The Cup Converter exists to take that particular chore off your hands.
Your data stays on your machine. Once the page has loaded you could disconnect entirely and it would still work.
Field definitions, the method, and a worked example from the default values are all set out further down the page.
What do the Cup Converter fields mean?
The Cup Converter uses 3 inputs. It opens with a complete example loaded, which is usually the quickest way to understand what a field means.
| Field | What to enter | Default |
|---|---|---|
| Value | required | 1 |
| From | choose from Millilitre (mL), Centilitre (cL), Litre (L), Cubic metre (m³), Cubic centimetre (cm³) or Cubic inch (in³) | Cup (US) (cup) |
| To | choose from Millilitre (mL), Centilitre (cL), Litre (L), Cubic metre (m³), Cubic centimetre (cm³) or Cubic inch (in³) | Millilitre (mL) |
How does the Cup Converter work?
Both units are converted through volume's base unit (L), so any of the 19 units in the dropdowns can be paired in either direction without loss of accuracy.
Exact definitions are preferred throughout: the metre, the inch and the pound all have them. Only where a unit depends on a measured constant is an accepted published value substituted.
Worked example
These are the values the Cup Converter loads by default, and the result it produces from them. The numbers below come straight from the default inputs, so you can verify them against the live tool.
| Value | 1 |
|---|---|
| From | Cup (US) (cup) |
| To | Millilitre (mL) |
| Result | 236.5882365 mL |
|---|---|
| How it was calculated | 1 cup = 236.5882365 mL, so 1 × 236.5882365 = 236.5882365 mL |
| Reverse conversion | 0.0042267528 cup (if you meant 1 mL) |
The cup
The US cup is defined as exactly 236.5882365 millilitres (8 US fluid ounces), but "cup" is not a single international standard, which makes it one of the more error-prone units in recipe conversion.
Worth knowing
- Australia, New Zealand and Canada commonly use a "metric cup" of exactly 250 mL, which is neither the US cup nor a rounded version of it: a recipe using "cups" without stating which standard can differ by about 5.7% depending on which cup was meant.
- The UK doesn’t widely use "cups" as a standard cooking measure at all, relying instead on weight (grams) for dry ingredients, which is generally more accurate for baking anyway, since a "cup" of flour can vary noticeably in actual weight depending on how it’s scooped and packed.
- For a recipe that matters (bread, pastry), weighing ingredients on a scale rather than converting cup measurements avoids the compounding uncertainty of both the cup-standard ambiguity and the scoop-density variability.
Definitions: BIPM SI Brochure · NIST reference on units
How to use it
- Type Value.
- Pick a value for From: the options are Millilitre (mL), Centilitre (cL), Litre (L), Cubic metre (m³), Cubic centimetre (cm³) or Cubic inch (in³).
- Pick a value for To: the options are Millilitre (mL), Centilitre (cL), Litre (L), Cubic metre (m³), Cubic centimetre (cm³) or Cubic inch (in³).
- The results panel stays in sync with the form as you edit it.
- Look at Result, How it was calculated and Reverse conversion in the output panel.
- To keep the result, either copy the link or print the page. Both preserve what is on screen.
What this tool does not do
- Conversion factors use SI definitions; some industries use their own rounded factors.
- Repeated conversions compound rounding, so convert once from the original value where possible.
- It handles the common case well and the unusual case literally.
- Garbage in, garbage out: confirm each figure means what you think it does before trusting the result.
Frequently asked questions
Value, From and To. That is the whole form. Defaults are loaded for all of them, so the form is usable immediately, without filling anything in first.
With the values loaded when the page opens, result comes out as 236.5882365 mL. Try changing one value. The answer refreshes without a page reload.
It never leaves the tab. The page does the work itself rather than asking a server to.
It is free with no conditions: no sign-up, and no limit on how often you use it.
It follows the standard definition for this operation, so the result matches what a reference implementation would give.