Free ounces to ml calculator
Enter fluid ounces — this ounces to mL converter handles both US (29.574 mL) and UK Imperial (28.413 mL) fluid ounces so your recipe measurements are always accurate, updated live, as you type.
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Volume-to-weight conversions are approximate and vary by ingredient brand, moisture, and packing method.
Results are estimates. Consult a professional.
How the fluid ounces to mL converter works
A fluid ounce (fl oz) is a unit of volume, not weight. The complication is that two countries call their fluid ounce by the same name but define it differently. The US fluid ounce is slightly larger than the UK (imperial) fluid ounce — a difference of about 4% that is irrelevant for a splash of vanilla but matters for a full cup or more. Unless a recipe is from the UK or explicitly says 'imperial', assume US fluid ounces.
Worked example: scaling a cocktail recipe
Marcus is scaling up a mocktail recipe for a party. The original US recipe calls for 6 fl oz of fresh lemon juice but his measuring jug is marked in millilitres only. He needs the mL equivalent so he can pour directly from the jug.
Fluid ounces to mL — US and UK comparison
The table gives both US and UK fluid ounce equivalents. For the full-cup mark (8 fl oz), the difference is about 9 mL — noticeable in baking and fermentation. For volumes of 4 fl oz or less, the two systems differ by less than 5 mL.
| Fl oz | US mL | UK mL | Common measure |
|---|---|---|---|
| ½ fl oz | 14.79 mL | 14.21 mL | 1 tablespoon (US) |
| 1 fl oz | 29.57 mL | 28.41 mL | Shot glass (standard) |
| 2 fl oz | 59.15 mL | 56.83 mL | ¼ US cup |
| 3 fl oz | 88.72 mL | 85.24 mL | — |
| 4 fl oz | 118.29 mL | 113.65 mL | ½ US cup |
| 6 fl oz | 177.44 mL | 170.48 mL | ¾ US cup |
| 8 fl oz | 236.59 mL | 227.30 mL | 1 US cup |
| 12 fl oz | 354.88 mL | 340.96 mL | 1 can of soda (US) |
| 16 fl oz | 473.18 mL | 454.61 mL | 1 US pint |
| 32 fl oz | 946.35 mL | 909.22 mL | 1 US quart |
Source: NIST SP 811; UK Weights and Measures Act 1985. US fl oz = 29.5735 mL; UK fl oz = 28.4131 mL. Differences accumulate with volume — at 32 fl oz the systems differ by 37 mL.
Tips for working with fluid ounces and millilitres
The fl oz–mL conversion is one of the most common in international cooking, bartending, and food manufacturing. These habits make it feel automatic.
- Check the recipe origin before converting — a UK food blog, a Delia Smith cookbook, or a British meal-kit box will use imperial fluid ounces (28.41 mL); a US recipe, a Serious Eats article, or a US meal-kit uses US fluid ounces (29.57 mL). The URL domain or writer's nationality is usually a reliable clue.
- Memorise 30 mL per US fl oz for quick estimates — the true value is 29.57 mL, but rounding up to 30 mL/fl oz is only 1.4% high and works fine for casual cooking, cocktails, and shopping comparisons.
- For coffee and espresso, use the metric side — specialty coffee ratios (espresso yield, brew ratios) are expressed in grams and millilitres by the Specialty Coffee Association. Use the mL reading directly rather than converting to fl oz and back.
- Bottle and can labels show both units in the US — a US soda can labelled '12 fl oz / 355 mL' confirms the US fl oz conversion at a glance: 12 × 29.5735 = 354.88 mL, rounded to 355 mL on the can.
- Use a jug with dual markings for international recipes — measuring jugs marked in both fl oz and mL eliminate all conversion error for liquid measures. They are widely available and useful whenever you cook from recipes in different regional traditions.
Accuracy and limitations
Both conversion factors (29.5735295625 mL for US fl oz; 28.4130625 mL for UK imperial fl oz) are exact defined values, not measured approximations. The calculator applies them at full floating-point precision before displaying a rounded result, so the arithmetic is as accurate as the definition allows.
This converter handles US fluid ounces and UK imperial fluid ounces only. It does not handle the Australian tablespoon (20 mL), the Canadian cup (250 mL), or the older US 'wine ounce' (1/16 US pint = 29.57 mL, which happens to match the modern US fl oz). For nutrition labelling in the US, 'serving' fluid ounces are always US fluid ounces. For spirits and wine in the UK, volumes are labelled in mL by law, so no conversion is needed.
Liquid volume terms defined
About this fluid ounces to mL converter
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