How do you use this tool?
- Enter a value in milliliters to convert to US fluid ounces — result appears instantly.
- Or enter a value in fluid ounces to convert to milliliters.
- Refer to the table below for common beverage and packaging sizes.
- Note the US fl oz vs. Imperial fl oz toggle if you need UK measurements.
What This Tool Does
This converter handles milliliters ↔ US fluid ounces in both directions with full precision. It is particularly useful for recipe scaling, beverage sizing, pharmaceutical dosing, and cosmetics labeling — all contexts where the US requires dual-unit labeling (mL and fl oz) on packaging.
How Do You Convert Milliliters to US Fluid Ounces?
US fl oz = mL ÷ 29.5735295625
mL = US fl oz × 29.5735295625
The US fluid ounce is defined as exactly 1/128 of a US liquid gallon. Since a US gallon is exactly 231 cubic inches, and one inch is exactly 2.54 cm, the mL equivalent works out to the precise value above.
Imperial Fluid Ounce (UK)
Imperial fl oz = mL ÷ 28.4130625
The Imperial fluid ounce is 1/20 of a UK pint, which is 1/8 of an Imperial gallon (4.54609 L). It is slightly smaller than the US fluid ounce.
What Are Common Reference Sizes?
| Volume | mL | US fl oz | US Kitchen Equivalent |
|---|---|---|---|
| 1 tsp | 4.93 mL | 0.167 fl oz | 1 teaspoon |
| 1 tbsp | 14.79 mL | 0.5 fl oz | 1 tablespoon |
| 1 fl oz | 29.57 mL | 1 fl oz | 2 tablespoons |
| ¼ cup | 59.15 mL | 2 fl oz | ¼ cup |
| ½ cup | 118.3 mL | 4 fl oz | ½ cup |
| 1 cup | 236.6 mL | 8 fl oz | 1 cup |
| 1 pint (US) | 473.2 mL | 16 fl oz | 1 pint |
| 1 quart | 946.4 mL | 32 fl oz | 1 quart |
| 1 liter | 1,000 mL | 33.81 fl oz | ~4.2 cups |
| 1 gallon | 3,785 mL | 128 fl oz | 4 quarts |
What Are Common Use Cases?
Beverage Sizes in the US
US beverage packaging relies on fl oz for labeling but manufacturers design around metric sizes. Common sizes and their equivalents:
| Beverage | mL | fl oz |
|---|---|---|
| Small water bottle | 250 mL | 8.45 fl oz |
| Standard water bottle | 500 mL | 16.9 fl oz |
| Standard soda can | 355 mL | 12 fl oz |
| Energy drink (standard) | 473 mL | 16 fl oz |
| Coffee (grande, Starbucks) | 473 mL | 16 fl oz |
| Soda bottle (small) | 591 mL | 20 fl oz |
| Standard wine pour | 148 mL | 5 fl oz |
| Pint of beer | 473 mL | 16 fl oz |
| Wine bottle | 750 mL | 25.36 fl oz |
| Spirits bottle (fifth) | 750 mL | 25.36 fl oz |
| Spirits bottle (liter) | 1,000 mL | 33.81 fl oz |
Recipe Conversion (Metric to US)
International recipes (especially European and Australian) give liquid measurements in mL. US recipes use cups and fl oz. The critical conversions:
- 250 mL ≈ 1 cup (actually 8.45 fl oz — close enough for cooking, not baking)
- 100 mL ≈ 3.38 fl oz ≈ 6.75 tablespoons
- For baking, use exact mL measurements with a kitchen scale or measuring cup with both scales
Medicine and Supplement Dosing
Liquid medications in the US are typically dosed in mL on the label and measured with calibrated syringes or dosing cups. The FDA requires mL-only markings on pediatric liquid medicine dosing devices since 2011 to reduce dosing errors.
Common doses:
- Children’s acetaminophen: 5 mL (0.17 fl oz) per dose
- Adult liquid antacid: 15–30 mL (0.5–1.0 fl oz) per dose
- Cough syrup: 10–15 mL (0.34–0.51 fl oz) per dose
Never use household teaspoons for medication — they vary from 3 to 7 mL.
Cosmetics and Personal Care
TSA carry-on limits allow liquids in containers of 3.4 fl oz (100 mL) or less, all fitting in one quart-sized bag. Cosmetics sold in the US display both mL and fl oz on packaging by FDA regulation. Standard sizes:
| Product | Typical Size |
|---|---|
| Travel shampoo | 75–100 mL (2.5–3.4 fl oz) |
| Foundation | 30 mL (1.0 fl oz) |
| Perfume (travel) | 30–50 mL (1.0–1.7 fl oz) |
| Skincare serum | 15–30 mL (0.5–1.0 fl oz) |
| Full-size shampoo | 355 mL (12 fl oz) |
When Does the US vs. Imperial Units Difference Matter?
A 4% difference sounds small, but in large-batch cooking or pharmaceutical contexts it compounds. If a UK recipe calls for 10 Imperial fl oz and you use US fl oz:
10 Imperial fl oz × 28.4131 mL = 284.1 mL 10 US fl oz × 29.5735 mL = 295.7 mL
Difference: 11.6 mL — about 2.5 teaspoons. For baking a single cake, negligible. For a 50-gallon batch production, it becomes a significant systematic error.
Frequently Asked Questions
Why does the US use fl oz instead of mL?
The US retained fluid ounces from the British Imperial system used at the time of American independence. While US science and medicine use mL, consumer packaging and recipes kept the customary system. Dual labeling (both units) is required on US food and beverage products by FDA regulation.
Is an fl oz the same as a weight ounce?
No. Fluid ounces measure volume; weight ounces measure mass. 1 fl oz of water weighs approximately 1.04 ounces (29.6 grams) — close but not the same. Denser liquids (like honey or syrup) weigh more per fluid ounce.
How many mL are in a shot?
A standard US shot is 1.5 fl oz = 44.4 mL. A “jigger” (common bartending tool) holds 1.5 fl oz on one side and 1.0 fl oz (29.6 mL) on the other. Some establishments define a shot as 1.0 fl oz (29.6 mL) — the definition varies.
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