Fluid ounce to Milliliter Converter

Convert fluid ounces to milliliters with our free online volume converter.

Quick Answer

1 Fluid ounce = 29.57353 milliliters

Formula: Fluid ounce × conversion factor = Milliliter

Use the calculator below for instant, accurate conversions.

Our Accuracy Guarantee

All conversion formulas on UnitsConverter.io have been verified against NIST (National Institute of Standards and Technology) guidelines and international SI standards. Our calculations are accurate to 10 decimal places for standard conversions and use arbitrary precision arithmetic for astronomical units.

Last verified: February 2026Reviewed by: Sam Mathew, Software Engineer

Fluid ounce to Milliliter Calculator

How to Use the Fluid ounce to Milliliter Calculator:

  1. Enter the value you want to convert in the 'From' field (Fluid ounce).
  2. The converted value in Milliliter will appear automatically in the 'To' field.
  3. Use the dropdown menus to select different units within the Volume category.
  4. Click the swap button (⇌) to reverse the conversion direction.
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How to Convert Fluid ounce to Milliliter: Step-by-Step Guide

Converting Fluid ounce to Milliliter involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Fluid ounce = 29.57353 milliliters

Example Calculation:

Convert 10 fluid ounces: 10 × 29.57353 = 295.7353 milliliters

Disclaimer: For Reference Only

These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.

Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.

What is a Fluid ounce and a Milliliter?

The fluid ounce (symbol: fl oz or fl. oz.) is a unit of volume used primarily in the United States for measuring liquids.

US Fluid Ounce (Standard in America)

US fluid ounce = exactly 29.5735295625 milliliters

Defined as: 1/128 of a US gallon

Mathematical relationships:

  • 2 tablespoons = 1 fluid ounce
  • 8 fluid ounces = 1 cup
  • 16 fluid ounces = 1 pint
  • 32 fluid ounces = 1 quart
  • 128 fluid ounces = 1 gallon

Imperial Fluid Ounce (UK)

Imperial fluid ounce = exactly 28.4130625 milliliters (about 4% smaller than US)

Defined as: 1/160 of an Imperial gallon

Key difference: The Imperial gallon (4.546 L) is larger than the US gallon (3.785 L), but divided into more fluid ounces, making each Imperial fluid ounce slightly smaller than the US version.

Fluid Ounce vs. Weight Ounce

This is the most common source of confusion:

Fluid ounce (fl oz): Measures volume (capacity/space)

  • Used for: liquids (water, milk, juice, oil)
  • 1 fl oz = 29.57 mL
  • Measured with measuring cups

Ounce (oz): Measures weight/mass

  • Used for: solid foods (flour, sugar, meat, cheese)
  • 1 oz = 28.35 grams
  • Measured with a scale

For water only: 1 fluid ounce of water weighs approximately 1.04 ounces by weight. This near-equivalence was intentional historically but leads to confusion because it doesn't apply to other liquids.

Example of the difference:

  • 8 fl oz of water weighs about 8.3 oz (by weight)
  • 8 fl oz of honey weighs about 12 oz (honey is denser)
  • 8 fl oz of vegetable oil weighs about 7.6 oz (oil is less dense)

The milliliter (symbol: mL or ml) is a unit of volume equal to exactly one-thousandth of a liter (1/1000 L or 0.001 L). Critically, 1 milliliter equals exactly 1 cubic centimeter (1 cm³ or 1 cc).

The milliliter is part of the International System of Units (SI) and uses the metric prefix "milli-" meaning one-thousandth (from Latin mille, "thousand").

Mathematical Relationships

1 milliliter equals:

  • 0.001 liters (L)
  • 1 cubic centimeter (cm³ or cc) exactly
  • 0.000001 cubic meters (m³)
  • 0.033814 US fluid ounces (fl oz)
  • 0.035195 UK fluid ounces (imperial)
  • 0.202884 teaspoons (tsp)
  • 0.067628 tablespoons (tbsp)

Key water relationship:

  • 1 mL of water weighs 1 gram (at 4°C, maximum density)

This elegant relationship makes metric conversions trivial for water-based solutions.

Milliliter = Cubic Centimeter (cc)

Perfect equivalence: 1 mL = 1 cm³ = 1 cc (all three are identical)

Why this matters:

  • Medical syringes often marked in "cc" (cubic centimeters) = milliliters
  • Engine displacement: "2000 cc engine" = 2000 mL = 2.0 L
  • Laboratory glassware uses both mL and cm³ interchangeably
  • A cube with 1 cm sides (1 cm × 1 cm × 1 cm) holds exactly 1 mL

Symbol variations:

  • mL (preferred in scientific publishing—avoids confusion with number "1")
  • ml (common in everyday use)
  • cc (common in medical and automotive contexts)

Why Milliliters?

While the liter is the base metric unit for volume, milliliters are more practical for everyday measurements:

Perfect human scale: Most cooking ingredients, medications, and beverage servings fall into the 5-500 mL range, avoiding decimals.

Avoids decimal confusion: "250 milliliters of milk" is clearer than "0.25 liters of milk" for most people.

Universal adoption: Used in 195+ countries for recipes, medicine, beverages, and laboratory work.

Note: The Fluid ounce is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Milliliter belongs to the metric (SI) system.

History of the Fluid ounce and Milliliter

Medieval Origins: Weight to Volume

Weight-Based Liquid Trade: In medieval England, wine, ale, and other liquids were originally sold by weight using the avoirdupois ounce (28.35 grams for weight).

Practical Problem: Weighing liquids was impractical for taverns and merchants who needed to pour drinks quickly. They needed a volume measurement.

Solution: The fluid ounce was created to represent the volume that a certain weight of liquid would occupy. For water, this created a convenient relationship: 1 fluid ounce of water weighs approximately 1 ounce.

1707: Wine Gallon Standardization (Colonial America)

Queen Anne's Wine Gallon: In 1707, England standardized the wine gallon at exactly 231 cubic inches. The fluid ounce was defined as 1/128 of this wine gallon.

American Adoption: When the United States gained independence, it retained the wine gallon system, including the fluid ounce as 1/128 of a gallon.

1824: Imperial System Divergence

British Imperial System: In 1824, Britain adopted the Imperial system, replacing the wine gallon with the larger Imperial gallon (277.42 cubic inches instead of 231).

Two Different Fluid Ounces:

  • US fluid ounce: Remained 1/128 of the wine gallon (29.57 mL)
  • Imperial fluid ounce: Became 1/160 of the Imperial gallon (28.41 mL)

This divergence created confusion that persists today, especially in international recipes and product labeling.

1959: International Agreement

Gallon Defined in Metric: The 1959 international yard and pound agreement defined the US gallon as exactly 231 cubic inches, which equals exactly 3.785411784 liters.

Fluid Ounce Fixed: This automatically defined the US fluid ounce as exactly 1/128 of 3.785411784 liters = 29.5735295625 milliliters.

Modern Usage

US Standard: The United States continues to use fluid ounces extensively for beverages, recipes, and product labeling.

UK Transition: The United Kingdom officially adopted the metric system but still uses Imperial fluid ounces alongside milliliters in some contexts (especially pints in pubs—568 mL).

Global Context: Most of the world uses milliliters and liters exclusively. Only the US, Myanmar, and Liberia primarily use non-metric volume units.

French Revolution: Birth of the Liter (1795)

Metric System Creation: The milliliter's story begins with the French Revolution's creation of the liter in 1795.

Water-Based Definition: One liter was originally defined as the volume occupied by one kilogram of pure water at maximum density (approximately 4°C or 39°F).

Elegant Interconnection:

  • 1 liter of water = 1 kilogram = 1,000 grams
  • 1 milliliter of water = 1 gram
  • 1 milliliter = 1 cubic centimeter

This made the metric system beautifully self-consistent—volume, mass, and spatial dimensions all linked through water.

Etymology: The word "liter" comes from the obsolete French unit "litron," which was derived from Medieval Latin "litra" (a unit of mass).

The Medieval Litron: A Pre-Metric Precursor

Before the French Revolution standardized the liter, the "litron" was a measure for grain and salt.

  • The Royal Litron: In the 17th century, the litron was roughly equivalent to 0.81 liters. However, because it was often measured using wooden boxes that could warp with humidity, the volume of a litron changed with the seasons.
  • The Tax Man's Litron: French peasants often had to pay their taxes in litrons of grain. This created a massive incentive for the crown to "expand" the litron while the peasants tried to "shrink" it, a measurement war that only ended with the precision of the metric milliliter.

The Milliliter in 19th Century Pharmacy

As "Apothecary" shops evolved into modern pharmacies, the "Drop" became a liability.

  • The Graduated Minim: Pharmacists used a 1-minim dropper, which was supposed to be 1/60th of a fluid dram. However, because the viscosity of oils versus tinctures resulted in different drop sizes, pharmacists pushed for the adoption of the milliliter as the only legally defensible unit for liquid drugs.

The Prefix "Milli-"

Latin Origin: "Milli-" comes from the Latin "mille" meaning "thousand."

Meaning: Milli- means one-thousandth (1/1000 or 0.001).

Other milli- units:

  • Millimeter: 1/1000 meter
  • Milligram: 1/1000 gram
  • Millisecond: 1/1000 second
  • Milliliter: 1/1000 liter

19th Century: Global Spread

1875: Metre Convention: The Treaty of the Metre established international cooperation on measurement standards. The liter (and milliliter) became recognized internationally.

Scientific Adoption: Laboratories worldwide embraced milliliters for precise liquid measurements, replacing inconsistent local units.

Medical Use: By the late 1800s, medicine had standardized on milliliters (or cubic centimeters/cc) for drug dosages and liquid medicines.

1901: Redefinition

Precision Refinement: In 1901, the liter was redefined as the volume of 1 kg of pure water at maximum density under standard atmospheric pressure. This made the liter slightly larger than 1 cubic decimeter (by about 28 parts per million).

1964: Modern Definition

CIPM Decision: The International Committee for Weights and Measures (CIPM) redefined the liter as exactly one cubic decimeter (1 dm³).

Impact on milliliters: 1 milliliter = exactly 1 cubic centimeter (1 cm³), eliminating any tiny discrepancy.

Current definition: The milliliter is now purely geometric—the volume of a cube with 1 cm sides—rather than water-based.

Common Uses and Applications: fluid ounces vs milliliters

Explore the typical applications for both Fluid ounce (imperial/US) and Milliliter (metric) to understand their common contexts.

Common Uses for fluid ounces

Beverage Industry Standard

Product Labeling: US beverages required to show fluid ounces:

  • "Contents: 12 fl oz (355 mL)"
  • "Serving size: 8 fl oz (240 mL)"
  • Dual labeling helps metric-using countries

Serving Sizes: Standardized for nutrition labels:

  • Soft drinks: 8 fl oz serving (though cans are 12 fl oz)
  • Juice: 8 fl oz serving
  • Energy drinks: varies, often 8 fl oz

Bar and Restaurant:

  • Draft beer: served in 12 fl oz, 16 fl oz (pint), 20 fl oz sizes
  • Wine by the glass: 5 fl oz, 6 fl oz, 9 fl oz pours
  • Mixed drinks: recipes measured in fl oz (jiggers)

Cooking and Recipe Instructions

American Recipes: Nearly all US recipes use fluid ounces and cups:

  • "Add 4 fl oz milk (1/2 cup)"
  • "Pour in 8 fl oz chicken stock (1 cup)"
  • Cups are more common, but fl oz appears on measuring cups

Liquid Measuring Cups: Marked with both:

  • Fluid ounces: 2, 4, 6, 8 fl oz markings
  • Cups: 1/4, 1/2, 3/4, 1 cup markings
  • Milliliters: 50, 100, 150, 200, 250 mL markings

Recipe Scaling: Fluid ounces make doubling/halving easy:

  • Original: 8 fl oz
  • Double: 16 fl oz
  • Half: 4 fl oz

Nutrition Facts and Food Labeling

Serving Size: US nutrition labels show fluid ounces:

  • "Serving Size: 8 fl oz (240 mL)"
  • "Servings Per Container: About 2 (16 fl oz bottle)"

Comparison Shopping: Unit pricing often per fluid ounce:

  • "Price per fl oz: $0.15"
  • Helps consumers compare different package sizes

Dietary Guidelines: Recommendations in fluid ounces:

  • Water intake: 64 fl oz (8 cups) per day common guideline
  • Juice limit: no more than 4-6 fl oz daily for children

Bartending and Mixology

Cocktail Recipes: Professional bartenders measure in fl oz:

  • Margarita: 2 fl oz tequila, 1 fl oz lime juice, 1 fl oz triple sec
  • Martini: 2.5 fl oz gin, 0.5 fl oz vermouth
  • Old Fashioned: 2 fl oz whiskey, plus bitters and sugar

Bar Tools:

  • Jigger: double-sided measuring cup (1 fl oz / 1.5 fl oz or 1 fl oz / 2 fl oz)
  • Shot glass: 1.5 fl oz standard (though varies)
  • Speed pourer: trained bartenders pour accurate fl oz by count

Standard Drink Definition: US defines standard drink as:

  • 1.5 fl oz distilled spirits (40% ABV)
  • 5 fl oz wine (12% ABV)
  • 12 fl oz beer (5% ABV)

Cosmetics and Personal Care

Product Sizing: Cosmetics sold in fluid ounces:

  • Perfume: 0.5 fl oz, 1 fl oz, 1.7 fl oz, 3.4 fl oz
  • Foundation: 1 fl oz, 1.7 fl oz typical
  • Shampoo/conditioner: 8 fl oz, 12 fl oz, 16 fl oz, 32 fl oz

TSA Liquid Limit: Air travel restrictions:

  • Maximum container: 3.4 fl oz (100 mL)
  • Total carry-on: 1 quart bag (32 fl oz capacity)

Travel Sizes: Products marketed as "TSA-friendly":

  • 3 fl oz or smaller containers

When to Use milliliters

Medicine and Pharmacology

Prescription Medications: Liquid medications measured in milliliters:

  • Antibiotics: "Take 10 mL twice daily"
  • Cough syrup: "Take 15 mL every 4-6 hours"
  • Pain relievers: "Give 5 mL per dose for children"

Dosing Precision: Milliliters allow accurate dosing:

  • Pediatric doses often require precision to 0.5 mL
  • Adult doses typically 5-30 mL range
  • Measuring spoons or syringes marked in mL

IV Fluids: Hospital IV bags measured in mL:

  • Saline drip: 1,000 mL bag, infused over hours
  • Medication delivery: 50-250 mL piggyback bags
  • Fluid intake/output: tracked in mL for patient monitoring

Cooking Worldwide

Global Recipe Standard: Most countries use milliliters for liquid ingredients:

  • "Add 250 mL milk"
  • "Mix in 30 mL soy sauce"
  • "Drizzle with 45 mL olive oil"

Kitchen Measuring Tools:

  • Liquid measuring cups: marked in mL (and fluid ounces in US)
  • Measuring spoons: 1.25 mL, 2.5 mL, 5 mL, 15 mL
  • Kitchen scale with liquid mode: measures mL for water-based liquids

Precision Baking: Professional bakers prefer milliliters for consistency:

  • Eliminates meniscus reading errors
  • Repeatable results
  • Easy scaling (double recipe = double all mL measurements)

Beverage Industry

Product Labeling: Beverages worldwide labeled in milliliters:

  • "Contents: 355 mL (12 fl oz)"
  • "Serving size: 250 mL"
  • "Servings per container: 4 (1,000 mL bottle)"

Alcohol Content: "Standard drink" defined in mL in many countries:

  • Australia: 10 mL pure alcohol = 1 standard drink
  • UK: 8 mL (10g) pure alcohol = 1 unit
  • US: 14 mL (17.7g) pure alcohol = 1 standard drink

Bartending: Cocktail recipes use milliliters:

  • Jigger: 30 mL (1 oz) or 45 mL (1.5 oz)
  • Recipes: "45 mL vodka, 15 mL lime juice, 10 mL simple syrup"

Laboratory Science

Chemistry: Milliliters essential for chemical reactions:

  • Titrations: measuring acid/base volumes to 0.1 mL
  • Solution preparation: "Dissolve in 500 mL solvent"
  • Concentration: moles per liter (mol/L or M)

Biology: Cell culture and biological assays:

  • Cell culture media: 10-50 mL per flask
  • PCR reactions: measured in microliters (µL), 1 µL = 0.001 mL
  • Biological samples: typically 0.5-5 mL volumes

Physics: Density measurements use mL:

  • Density = mass (grams) ÷ volume (milliliters) = g/mL
  • Water: 1 g/mL at 4°C
  • Alcohol: 0.79 g/mL
  • Mercury: 13.6 g/mL

Cosmetics and Personal Care

Product Packaging: Cosmetics labeled in milliliters:

  • Perfume: 30 mL, 50 mL, 100 mL bottles
  • Foundation: 30-50 mL bottles
  • Shampoo: 250 mL, 500 mL, 1,000 mL bottles
  • Travel sizes: typically 100 mL or less (TSA limit)

Conversion Table: Fluid ounce to Milliliter

Fluid ounce (fl oz)Milliliter (mL)
0.514.787
129.574
1.544.36
259.147
5147.868
10295.735
25739.338
501,478.677
1002,957.353
2507,393.382
50014,786.765
1,00029,573.53

People Also Ask

How do I convert Fluid ounce to Milliliter?

To convert Fluid ounce to Milliliter, enter the value in Fluid ounce in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our volume converter page to convert between other units in this category.

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What is the conversion factor from Fluid ounce to Milliliter?

The conversion factor depends on the specific relationship between Fluid ounce and Milliliter. You can find the exact conversion formula and factor on this page. Our calculator handles all calculations automatically. See the conversion table above for common values.

Can I convert Milliliter back to Fluid ounce?

Yes! You can easily convert Milliliter back to Fluid ounce by using the swap button (⇌) in the calculator above, or by visiting our Milliliter to Fluid ounce converter page. You can also explore other volume conversions on our category page.

Learn more →

What are common uses for Fluid ounce and Milliliter?

Fluid ounce and Milliliter are both standard units used in volume measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our volume converter for more conversion options.

For more volume conversion questions, visit our FAQ page or explore our conversion guides.

All Volume Conversions

Liter to MilliliterLiter to Cubic meterLiter to Gallon (US)Liter to Gallon (UK)Liter to QuartLiter to CupLiter to Fluid ounceLiter to Cup (US)Liter to Pint (US)Milliliter to LiterMilliliter to Cubic meterMilliliter to Gallon (US)Milliliter to Gallon (UK)Milliliter to QuartMilliliter to CupMilliliter to Fluid ounceMilliliter to Cup (US)Milliliter to Pint (US)Cubic meter to LiterCubic meter to MilliliterCubic meter to Gallon (US)Cubic meter to Gallon (UK)Cubic meter to QuartCubic meter to CupCubic meter to Fluid ounceCubic meter to Cup (US)Cubic meter to Pint (US)Gallon (US) to LiterGallon (US) to MilliliterGallon (US) to Cubic meterGallon (US) to Gallon (UK)Gallon (US) to QuartGallon (US) to CupGallon (US) to Fluid ounceGallon (US) to Cup (US)Gallon (US) to Pint (US)Gallon (UK) to LiterGallon (UK) to MilliliterGallon (UK) to Cubic meterGallon (UK) to Gallon (US)Gallon (UK) to QuartGallon (UK) to CupGallon (UK) to Fluid ounceGallon (UK) to Cup (US)Gallon (UK) to Pint (US)Quart to LiterQuart to MilliliterQuart to Cubic meterQuart to Gallon (US)Quart to Gallon (UK)Quart to CupQuart to Fluid ounceQuart to Cup (US)Quart to Pint (US)Cup to LiterCup to MilliliterCup to Cubic meterCup to Gallon (US)Cup to Gallon (UK)Cup to QuartCup to Fluid ounceCup to Cup (US)Cup to Pint (US)Fluid ounce to LiterFluid ounce to Cubic meterFluid ounce to Gallon (US)Fluid ounce to Gallon (UK)Fluid ounce to QuartFluid ounce to CupFluid ounce to Cup (US)Fluid ounce to Pint (US)Cup (US) to LiterCup (US) to MilliliterCup (US) to Cubic meterCup (US) to Gallon (US)Cup (US) to Gallon (UK)Cup (US) to QuartCup (US) to CupCup (US) to Fluid ounceCup (US) to Pint (US)Pint (US) to LiterPint (US) to MilliliterPint (US) to Cubic meterPint (US) to Gallon (US)Pint (US) to Gallon (UK)Pint (US) to QuartPint (US) to CupPint (US) to Fluid ouncePint (US) to Cup (US)

Verified Against Authority Standards

All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.

NIST Volume Measurement

National Institute of Standards and TechnologyStandards for volume measurements

Last verified: February 19, 2026