Metric Teaspoons to Milliliters (tsp to mL)

1 metric teaspoon equals 5 milliliters exactly.

1 metric teaspoon = 5 milliliters

How to convert metric teaspoons to milliliters

To convert metric teaspoons to milliliters, multiply the number of metric teaspoons by 5. This factor is exact. To go the other way, multiply milliliters by 0.2.

milliliters = metric teaspoons × 5

Example: 10 metric teaspoons = 50 milliliters.

Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.

About these units

Metric Teaspoon (tsp)

Cooking & barCurrent unit

Exactly 5 mL, used in most countries.

Five milliliters is the metric teaspoon, a figure so tidy that it has become the working definition for medicine and food labels. The traditional British teaspoon was an imperial fluid drachm, one eighth of an imperial fluid ounce, about 3.55 milliliters, and the American one was 4.93 mL. US nutrition labeling law now defines a teaspoon as exactly 5 milliliters.

The 5 mL teaspoon matters most when dosing medicine. Kitchen spoons vary widely, with one Greek survey of 71 household teaspoons finding volumes from 2.5 to 7.3 mL, so measuring spoons, syringes and calibrated cups are the safer tools. It also anchors the metric cooking system: three teaspoons make a 15 mL tablespoon, and fifty fit in a 250 mL metric cup. Australia keeps a 5 mL teaspoon but counts four of them in its larger 20 mL tablespoon.

1 metric teaspoon = 0.005 liters (exactly).

Sources: Wikipedia: Teaspoon; 21 CFR 101.9: nutrition labeling household measures; Wikipedia: Metric cup

Milliliter (mL)

Metric (SI)Current unit

One thousandth of a liter, or exactly 1 cubic centimeter. Used for medicine, cooking and small containers.

Milliliters inherit everything from the liter, since the prefix simply means one thousandth. Because the liter is a cubic decimeter, a milliliter works out to exactly one cubic centimeter, a coincidence the metric system built in on purpose so that volume, length and mass interlock. One milliliter of water has a mass of about one gram, so a dosing syringe, a kitchen scale and a measuring jug can all be checked against one another.

Today milliliters dominate wherever small amounts must be measured precisely: medicine, flavorings, perfume, shampoo and the fine print on drink labels. Spelling is a mild regional split, with uppercase mL preferred in the United States, Canada and Australia and lowercase ml common in the UK and Europe. For scale, a US teaspoon is just under 5 mL, a US tablespoon is about 14.8 mL, and the US nutrition-label cup is exactly 240 mL, so one such cup is 240 of these tiny units.

1 milliliter = 0.001 liters (exactly).

Sources: Wikipedia: Litre; NIST SP 811, Appendix B.8: conversion factors for volume; 21 CFR 101.9: nutrition labeling household measures

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