Volume Converter

Volume Converter

Convert between millilitres, litres, fluid ounces, teaspoons, tablespoons, cups, pints, quarts, and gallons. Type in either field for instant bidirectional conversion, all units update simultaneously. Includes clinical IV and oral liquid dosing reference values.

Real-time all-unit display NIST-exact factors Clinical dosing presets
Volume Converter
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All units at once:

Millilitre (mL)-
Litre (L)-
US Fluid oz-
Teaspoon (tsp)-
Tablespoon (tbsp)-
US Cup-

🩺 Clinical dosing presets, click to load

Standard oral teaspoon
5 mL = 1 clinical tsp
Standard tablespoon
15 mL = 1 tbsp
30 mL oral syringe
30 mL ≈ 1 fl oz
100 mL IV minibag
100 mL = 3.38 fl oz
250 mL IV bag
250 mL = 0.25 L
1 L IV bag
1,000 mL = 1 L

Quick reference

1 mL= 0.0338 fl oz
1 fl oz= 29.574 mL
1 tsp= 4.929 mL
1 tbsp= 14.787 mL
1 US cup= 236.6 mL
1 L= 1,000 mL
1 US pint= 473.2 mL
1 US gallon= 3.785 L

Volume Conversion Reference

Accurate volume conversion is critical in clinical settings, particularly for oral liquid medications where doses are expressed in mL but patients measure in teaspoons or tablespoons, and for IV therapy where infusion bags are labelled in mL but flow rates must be calculated in mL/hr, the exact conversion our IV Drip Rate Calculator handles. This converter uses NIST-exact conversion factors for all US customary units.

Key Volume Conversion Factors

The figures below follow the NIST-published exact conversion factors for US customary volume units, not rounded approximations.

UnitmL EquivalentClinical Use
1 teaspoon (clinical)5.000 mLStandard for oral liquid prescribing; rounded from 4.929 mL for ease
1 US teaspoon (exact)4.929 mLNIST-exact value; used for precise calculations
1 tablespoon14.787 mL= 3 teaspoons; used in nutrition and compounding
1 US fluid ounce29.574 mLOral syringes, liquid medications in US labelling
1 UK fluid ounce28.413 mLDifferent from US, check label origin carefully
1 US cup236.588 mLNutritional labelling; hydration tracking
1 US pint473.176 mLBlood product volumes; fluid replacement reference
1 US gallon3,785.41 mLLarge-volume references; dialysis fluid volumes

Clinical vs. Exact Teaspoon

In clinical practice, 1 teaspoon = 5 mL is the universally used approximation for prescribing and dispensing oral liquid medications. The exact US teaspoon (4.929 mL) differs by less than 1.5%, which is clinically insignificant for most medications. However, for high-potency drugs or when precise compounding is required, the exact value should be used, per USP General Chapter 795 on nonsterile compounding standards. Our converter uses the exact NIST value (4.929 mL) for accuracy.

US vs. UK Volume Units

The US and UK both use fluid ounces and pints, but the values differ:

UnitUSUK (Imperial)
Fluid ounce29.574 mL28.413 mL
Pint473.18 mL (16 fl oz)568.26 mL (20 fl oz)
Gallon3,785.41 mL4,546.09 mL

When interpreting international drug labels or patient reports, always verify which measurement system is being used.

Frequently Asked Questions

How many mL is 1 teaspoon of medicine?+
For clinical purposes, 1 teaspoon of medicine = 5 mL. This is the standard approximation used in prescribing, dispensing, and patient instructions worldwide. When a prescription says "take 1 teaspoon," it means 5 mL. A standard oral medicine spoon or syringe marked in mL is the most accurate way to measure. Kitchen teaspoons vary in size and should not be used for drug dosing.
What is the difference between US and UK fluid ounces?+
A US fluid ounce = 29.574 mL; a UK (Imperial) fluid ounce = 28.413 mL. The difference is approximately 4%. For clinical drug labelling, US fluid ounces are used on US products and UK fluid ounces on UK products. Always check the label origin when converting. This converter includes both, select "UK Fluid Ounce" or "US Fluid Ounce" in the unit selector.
How do I convert mL to cups for nutrition tracking?+
1 US cup = 236.588 mL. To convert mL to cups, divide by 236.588. For example, 500 mL ÷ 236.588 = 2.11 cups. For daily water intake tracking, 8 cups per day ≈ 1,893 mL ≈ 1.9 L. For a personalised daily water intake calculation based on your weight and activity level, see our Daily Water Intake Calculator.

Related Tools on MediCalc Pro

For general unit conversion across weight, height, temperature, and more, see the Universal Unit Converter. For medication unit conversion, see the Medication Dose Converter.

References

⚠️ Clinical Note: Always use calibrated oral syringes or measuring cups for liquid medication doses. Household spoons vary significantly in volume and are not appropriate for drug dosing. A 5 mL oral syringe is the recommended tool for paediatric liquid medications.