Fluid-volume conversion
8 oz to mL: Exact Conversion and Cup Size Guide
236.59 mLfor 8 U.S. fluid ounces
Eight U.S. fluid ounces is usually rounded to 237 mL. A 240 mL label uses a different rounding convention, while imperial ounces and weight ounces require different calculations.
Quick answer
8 oz to mL at a Glance
The correct number depends on whether “oz” means U.S. liquid volume, imperial liquid volume, a food-label convention, or weight.
The Standard U.S. Answer
236.59milliliters, normally rounded to 237 mL. For the common search “8oz to ml,” this is the precise practical answer when “oz” means U.S. fluid ounces.
| Meaning of 8 oz | Milliliters | When it applies |
|---|---|---|
| 8 U.S. fluid ounces | 236.59 mL | U.S. customary liquid measurement |
| Rounded U.S. fluid ounces | 237 mL | Recipes and everyday conversion |
| U.S. nutrition labeling | 240 mL | FDA household-measure convention |
| 8 imperial fluid ounces | 227.30 mL | U.K./imperial liquid measure |
| 8 ounces by weight | No single answer | The ingredient’s density is required |
The underlying U.S. and imperial conversion factors are published in the NIST Guide to the SI.
Calculation method
How to Convert 8oz to mL
For U.S. liquid volume, multiply fluid ounces by 29.57353. Divide by the same factor to convert milliliters back to U.S. fluid ounces.
Fluid Ounces to Milliliters
8 × 29.57353 = 236.58824 mL
Rounded to two decimal places, the result is 236.59 mL. Rounded to the nearest whole milliliter, it is 237 mL.
Milliliters Back to Fluid Ounces
240 ÷ 29.57353 ≈ 8.12 U.S. fl oz
Multiplying by 30 is a convenient estimate. Use 29.57353 when you need the customary conversion rather than the rounded shortcut.
Why answers differ
236.59, 237 or 240 mL?
All three numbers can appear in legitimate contexts. The key is knowing whether the source is using an exact customary conversion, everyday rounding, or U.S. food-label rules.
Customary conversion
236.59 mLEight U.S. fluid ounces using the NIST factor of 29.57353 mL per fluid ounce.
Everyday rounding
237 mLThe same U.S. customary value rounded to the nearest whole milliliter.
Nutrition labeling
240 mLThe FDA convention treats one fluid ounce as 30 mL and one cup as 240 mL for nutrition labeling.
The FDA serving-size guidance explains the 30 mL-per-fluid-ounce and 240 mL-per-cup labeling convention. The 3.41 mL difference between 236.59 and 240 mL is about 1.4%.
Measurement systems
Volume, Imperial and Weight
Fluid ounces describe volume. A plain ounce can also describe mass, which cannot be converted to milliliters without density.
U.S. and imperial ounces differ
Eight U.S. fl oz is 236.59 mL; eight imperial fl oz is approximately 227.30 mL.
Do Not Mix Volume and Weight
Fluid ounce (fl oz) measures how much space a liquid occupies. Ounce (oz) can measure mass.
Eight weight ounces of honey, flour, oil, and water do not occupy the same volume. When density is known, use:
NIST lists one avoirdupois ounce as 28.34952 g, so 8 ounces by weight is 226.79616 g. That still does not establish volume until the material is identified.
Quick reference
Fluid Ounces to Milliliters
These values use U.S. fluid ounces and are rounded to two decimal places.
| U.S. fluid ounces | Milliliters | U.S. fluid ounces | Milliliters |
|---|---|---|---|
| 1 fl oz | 29.57 mL | 7 fl oz | 207.01 mL |
| 2 fl oz | 59.15 mL | 8 fl oz | 236.59 mL |
| 3 fl oz | 88.72 mL | 10 fl oz | 295.74 mL |
| 4 fl oz | 118.29 mL | 12 fl oz | 354.88 mL |
| 5 fl oz | 147.87 mL | 16 fl oz | 473.18 mL |
| 6 fl oz | 177.44 mL | 1 U.S. cup | 236.59 mL |
Packaging context
What 8 oz Means for a Paper Cup
For disposable drinkware, 8 oz is a nominal capacity label. In U.S.-oriented product language, it generally points to the 236.59-240 mL size class, but it does not establish exact dimensions, working fill, wall construction, or lid fit.
These dimensions describe one reviewed PaperBull double-wall example, not every 8 oz cup. See the complete paper cup dimensions and dieline guide for supplier-specific 8-16 oz measurements and artwork context.
Product routes
Compare 8 oz Paper Cups
Single-wall and double-wall cups are distinct products. Confirm current specifications, approved lids, artwork requirements and commercial terms for the selected item.
Compact paper hot cup
8 oz Single-Wall Cup
A lightweight product route for espresso-based drinks, small coffee servings, tea and custom-printed takeaway programs.
View the single-wall cup →
Insulated paper hot cup
8 oz Double-Wall Cup
A separate double-wall product route for smaller hot-drink portions where buyers want additional wall structure.
View the double-wall cup →Procurement check
Confirm More Than Capacity
Nominal capacity is a starting point. The usable cup-and-lid system must be checked around the actual drink and service workflow.
Verify the exact cup, capacity convention and approved components.- Name the product and construction. Identify the exact SKU and whether it is single wall, double wall or another verified format.
- Confirm the capacity convention. Ask whether the number is nominal, brimful or tied to a recommended fill.
- Record formed dimensions. Check rim diameter, base diameter, height and taper.
- Test working fill. Allow for foam, toppings, ice, mixing, movement and lid clearance.
- Match the approved lid. The 8 oz label alone cannot prove fit.
- Use the exact artwork dieline. Do not create print files from outside cup dimensions.
- Approve physical samples. Test the cup with real equipment, holders, carriers and service conditions.
Common questions
8 oz to mL FAQs
Quick answers separate exact liquid conversion from food-label rounding, weight and physical cup specifications.
How many mL is 8oz?
Eight U.S. fluid ounces is 236.59 mL, normally rounded to 237 mL. U.S. nutrition labeling commonly represents 8 fluid ounces as 240 mL.
Is 8 oz exactly 240 mL?
No under the exact U.S. customary conversion. The 240 mL value comes from the nutrition-label convention of 30 mL per fluid ounce.
How many mL is 8 imperial oz?
Eight imperial fluid ounces is approximately 227.30 mL, using 28.41306 mL per imperial fluid ounce.
Is 8 oz equal to one cup?
Eight U.S. fluid ounces equals one U.S. customary cup by volume. It is approximately 236.59 mL; nutrition labeling represents one cup as 240 mL.
How many mL is 8 oz of water?
If 8 oz means U.S. fluid ounces, it is 236.59 mL. If it means ounces by weight, volume requires density and the required precision.
Is an 8 oz coffee cup 237 or 240 mL?
Both may describe the same nominal size class. 237 mL is the rounded customary conversion; 240 mL is a common label and commercial convention.
Are all 8 oz paper cups the same size?
No. Capacity does not fix height, rim, base, taper, wall construction, working fill or lid profile.
Can I choose a lid from the 8 oz label?
No. Match the lid to the exact cup code and rim profile, then test the filled system.
Source transparency
Sources and Verification
Conversion values use government measurement references. Paper-cup dimensions remain supplier-specific.
- U.S. and imperial fluid-ounce factors, the U.S. cup value and the avoirdupois ounce factor: NIST Guide to the SI, Appendix B.8.
- Rounded U.S. household conversions: NIST approximate U.S.-to-metric conversion table.
- Nutrition-label household measures: FDA serving-size guidance, citing 21 CFR 101.9(b)(5)(viii).
- Supplier-specific 8 oz cup dimensions: PaperBull paper cup dimensions guide.
Need an 8 oz Cup Specification Confirmed?
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