This converter handles all common metric and US customary volume units: milliliters, liters, US fluid ounces, US cups, tablespoons, teaspoons, US pints, and US gallons. Enter a value, pick your units, and the result appears immediately. All conversions use the exact US customary definitions from NIST.
- 1 US fl oz = 29.5735 ml exactly (US definition; UK fl oz is 28.4131 ml).
- 1 US cup = 236.588 ml = 8 fl oz. 1 US gallon = 3,785.41 ml = 128 fl oz = 16 cups.
- 1 tbsp = 3 tsp = 14.787 ml. 1 tsp = 4.929 ml.
- Quick mental check: 1 liter is about 33.8 fl oz or just over 2 US pints (32 fl oz).
Specific volume converters
How to use our volume converter
Type a value in the input field, select the unit you are converting from, then select the unit you want. The result updates as you type. The swap button reverses the direction without retyping. Quick conversion buttons at the top jump straight to the most common pairs: ml to fl oz, fl oz to ml, cups to ml, and liters to gallons.
All calculations run locally in your browser. No data is sent anywhere. Results use exact conversion factors from NIST and BIPM definitions.
Metric volume units
The metric system measures volume in liters, with the milliliter (one-thousandth of a liter) as the practical everyday unit. The liter is not an SI base unit - the SI base unit of volume is the cubic meter (1 m³ = 1,000 L) - but the liter is accepted by BIPM for use with SI. It is used in almost every country for beverages, medicine, cooking, and fuel.
| Unit | Symbol | Milliliters (exact) | Common use |
|---|---|---|---|
| Liter | L | 1,000 ml | Beverages, fuel, cooking |
| Milliliter | ml | 1 ml | Medicine, nutrition, small measures |
| Centiliter | cl | 10 ml | Wine and spirits (Europe) |
| Deciliter | dl | 100 ml | Recipes in Scandinavia |
The milliliter is functionally equal to one cubic centimeter (1 ml = 1 cm³). This makes it easy to work with geometry: a 10 cm × 10 cm × 10 cm cube holds exactly 1 liter.
US customary volume units
The US customary system uses fluid ounces as the base unit for liquid volume, with pints, quarts, and gallons as larger containers. All these units are defined by NIST relative to the liter.
According to NIST, the US customary system is used in everyday commerce across all 50 US states, though science and medicine use metric units.
| Unit | Symbol | Milliliters (exact) | Fluid ounces | Common use |
|---|---|---|---|---|
| Gallon | gal | 3,785.41 ml | 128 fl oz | Fuel, milk jugs, large containers |
| Quart | qt | 946.353 ml | 32 fl oz | Large beverage containers |
| Pint | pt | 473.176 ml | 16 fl oz | Beer, berries, deli containers |
| Cup | cup | 236.588 ml | 8 fl oz | Recipes, measuring cups |
| Fluid ounce | fl oz | 29.5735 ml | 1 fl oz | Beverages, nutrition labels, recipes |
A note on UK vs US fluid ounces: a UK (imperial) fluid ounce is 28.4131 ml, about 4% smaller than the US fl oz (29.5735 ml). UK pints are also different - a UK pint is 568 ml (20 fl oz), while a US pint is 473 ml (16 fl oz). This converter uses US definitions throughout.
Cooking measurement units
US recipes use tablespoons and teaspoons as the smallest cooking measures. These units follow a strict hierarchy: 3 teaspoons = 1 tablespoon, 4 tablespoons = 1/4 cup, and 16 tablespoons = 1 cup. Knowing these relationships lets you scale recipes without a measuring cup.
| Unit | Milliliters | Teaspoons | Tablespoons | Cups |
|---|---|---|---|---|
| 1 teaspoon (tsp) | 4.929 ml | 1 | 1/3 | 1/48 |
| 1 tablespoon (tbsp) | 14.787 ml | 3 | 1 | 1/16 |
| 1/4 cup | 59.147 ml | 12 | 4 | 1/4 |
| 1/3 cup | 78.863 ml | 16 | 5.33 | 1/3 |
| 1/2 cup | 118.294 ml | 24 | 8 | 1/2 |
| 1 cup | 236.588 ml | 48 | 16 | 1 |
When I personally convert between metric and US cooking measures, I find the tablespoon-to-ml relationship the most practical anchor: 1 tbsp = roughly 15 ml. This mental shortcut is 1.4% high (the actual value is 14.787 ml), which is negligible for home cooking but significant for pharmaceutical compounding. But definitely saves you some time when you are cooking at home.
Dedicated volume conversion pages and formulas
Each page below focuses on a single conversion pair with a detailed reference table, formula, and worked examples:
| Conversion | Formula |
|---|---|
| Milliliters to Liters | L = ml ÷ 1,000 |
| Liters to Milliliters | ml = L × 1,000 |
| Milliliters to Fluid Ounces | fl oz = ml × 0.033814 |
| Fluid Ounces to Milliliters | ml = fl oz × 29.5735 |
| Oz to ml | ml = fl oz × 29.5735 |
| ml to oz | fl oz = ml × 0.033814 |
| Liters to Fluid Ounces | fl oz = L × 33.814 |
| Fluid Ounces to Liters | L = fl oz × 0.029574 |
| Liters to Gallons | gal = L × 0.264172 |
| Gallons to Liters | L = gal × 3.78541 |
| Cups to Milliliters | ml = cups × 236.588 |
| Milliliters to Cups | cups = ml × 0.004227 |
| Tablespoons to Milliliters | ml = tbsp × 14.7868 |
| Milliliters to Tablespoons | tbsp = ml × 0.067628 |
| Teaspoons to Milliliters | ml = tsp × 4.92892 |
| Milliliters to Teaspoons | tsp = ml × 0.202884 |
| Fluid Ounces to Pints | pints = fl oz ÷ 16 |
| Pints to Fluid Ounces | fl oz = pints × 16 |
| Pints to Gallons | gal = pints ÷ 8 |
| Gallons to Pints | pints = gal × 8 |
| Cups to Fluid Ounces | fl oz = cups × 8 |
| Fluid Ounces to Cups | cups = fl oz ÷ 8 |
Common volume conversions
Milliliters and fluid ounces
1 fl oz = 29.5735 ml. 1 ml = 0.033814 fl oz.
- 100 ml to fl oz: 100 × 0.033814 = 3.38 fl oz
- 355 ml to fl oz: 355 × 0.033814 = 12 fl oz (standard US can)
- 500 ml to fl oz: 500 × 0.033814 = 16.91 fl oz
- 750 ml to fl oz: 750 × 0.033814 = 25.36 fl oz (wine bottle)
Also see: ml to fl oz and fl oz to ml.
Liters and gallons
1 US gallon = 3.78541 L. 1 L = 0.264172 US gallons.
- 1 L to gallons: 0.264 gal
- 2 L to gallons: 0.528 gal
- 1 gal to liters: 3.785 L
- 5 gal to liters: 18.93 L (common for water cooler jugs)
Also see: liters to gallons and gallons to liters.
Cups and milliliters
1 US cup = 236.588 ml. 250 ml is not a cup - it is 1.057 cups (a metric cup used in some countries is 250 ml, but this converter uses the US cup).
- 1/2 cup to ml: 118.3 ml
- 1 cup to ml: 236.6 ml
- 2 cups to ml: 473.2 ml
- 4 cups to ml: 946.4 ml (nearly 1 liter)
Also see: cups to ml and ml to cups.
Quick reference table for volume conversions
The table below covers the most common volume conversions. Each row gives the exact multiplication factor and a worked numeric example.
| From | To | Multiply by | Example |
|---|---|---|---|
| ml | L | 0.001 | 500 ml × 0.001 = 0.5 L |
| L | ml | 1,000 | 1.5 L × 1,000 = 1,500 ml |
| ml | fl oz | 0.033814 | 355 ml × 0.033814 = 12 fl oz |
| fl oz | ml | 29.5735 | 8 fl oz × 29.5735 = 236.6 ml |
| L | fl oz | 33.814 | 1 L × 33.814 = 33.8 fl oz |
| L | gal | 0.264172 | 3.785 L × 0.264 = 1 gal |
| gal | L | 3.78541 | 1 gal × 3.785 = 3.785 L |
| cup | ml | 236.588 | 2 cups × 236.6 = 473.2 ml |
| tbsp | ml | 14.7868 | 4 tbsp × 14.79 = 59.1 ml |
| tsp | ml | 4.92892 | 1 tsp × 4.93 = 4.93 ml |
| pint | fl oz | 16 | 2 pints × 16 = 32 fl oz |
| gal | pints | 8 | 1 gal × 8 = 8 pints |
The US vs UK fl oz difference catches people most often when following UK recipes. I've seen this cause real problems when someone scales a UK cocktail recipe for a US audience - the fl oz amounts look the same on paper but represent different volumes. Always confirm whether a recipe uses US or UK measurements before converting.
Common mistakes in volume conversion
Confusing US and UK fluid ounces
A US fl oz is 29.5735 ml. A UK (imperial) fl oz is 28.4131 ml. They look identical on a label but differ by about 4%. If you're following a UK recipe that lists "fl oz" or if a UK-manufactured product shows volume in fl oz, the values are slightly different from the US equivalent. This converter uses US fl oz throughout.
Assuming 250 ml equals 1 cup
250 ml = 1.057 US cups, not 1 cup. The US cup is 236.588 ml. Some countries (Australia, Canada, metric recipes) use a "metric cup" of 250 ml. When you see "1 cup" in an American recipe, that's 236.6 ml. Using 250 ml adds about 5.6% extra per cup, which is noticeable in baking.
Mixing up tablespoons and teaspoons in conversions
1 tablespoon = 3 teaspoons = 14.787 ml. 1 teaspoon = 4.929 ml. When converting a recipe, doubling a tablespoon-based measurement and entering it as teaspoons gives a result that's 3× too high. Always confirm the unit before converting.
FAQs about converting volume units
How many ml is 1 fluid ounce?
1 US fluid ounce equals 29.5735 ml. This is the exact NIST definition. For quick mental math, 1 fl oz is roughly 30 ml (1.5% high) or exactly 29.57 ml (0.001% low). The UK imperial fluid ounce is different at 28.4131 ml.
How many ml is 1 cup?
1 US cup equals 236.588 ml, or approximately 236.6 ml. This is based on the US legal definition used for nutrition labeling (21 CFR 101.9). The Australian and Canadian metric cup is 250 ml, so check the recipe's country of origin when precision matters.
How many ml is 1 liter?
1 liter equals exactly 1,000 milliliters. This is an SI definition - "milli" means one-thousandth. 1 liter also equals 33.814 US fluid ounces, 4.227 US cups, 67.628 tablespoons, 0.264 US gallons, and 2.113 US pints.
How many fluid ounces is 1 liter?
1 liter equals 33.814 US fluid ounces. A quick way to remember: 1 liter is a little more than 2 US pints (which are 32 fl oz). The difference is 1.814 fl oz - about 2 tablespoons.
How many cups are in a gallon?
There are 16 US cups in 1 US gallon. The full US customary liquid hierarchy is: 1 gallon = 4 quarts = 8 pints = 16 cups = 32 gills = 128 fluid ounces = 3,785.41 ml.
What is the difference between a US fluid ounce and a UK fluid ounce?
A US fluid ounce is 29.5735 ml. A UK (imperial) fluid ounce is 28.4131 ml. The difference is about 4%. This matters when comparing UK and US product labels or following recipes from different countries. The UK has largely moved to metric for most purposes, so "fl oz" on a UK label is relatively rare today.
Quiz: how well do you know volume conversion?
1. How many milliliters are in 1 US fluid ounce?
2. A recipe calls for 2 cups of water. How many milliliters is that?
3. How many fluid ounces are in 1 US gallon?
4. 1 tablespoon equals how many teaspoons?
5. 500 ml is closest to how many US fluid ounces?