How many milliliters are in one teaspoon?

One US teaspoon equals exactly 4.92892159375 mL. For most practical purposes this rounds to 4.93 mL or simply 5 mL.

Is a teaspoon exactly 5 mL?

By convention in nutrition labeling and medicine, 1 teaspoon is rounded to 5 mL. The precise US customary value is 4.92892 mL — a difference of less than 1.5%, which matters for precise laboratory work but not typical cooking.

Does this use US or metric teaspoons?

This converter uses the US customary teaspoon (4.92892 mL). The metric teaspoon used in Australia and some other countries is exactly 5 mL. UK teaspoons also vary slightly.

How do I convert milliliters back to teaspoons?

Divide the mL value by 4.92892. You can also use the swap button in this tool to reverse the direction of conversion.

How many teaspoons are in a tablespoon?

There are 3 teaspoons in one US tablespoon (14.7868 mL total). A tablespoon is therefore exactly 14.7868 mL.

Teaspoons to Milliliters Converter

Name: Teaspoons to Milliliters Converter
Availability: InStock
Author: Nham Vu

Convert teaspoons to milliliters instantly — 1 US teaspoon equals exactly 4.92892 mL.

Teaspoons (tsp)

US customary teaspoon · 1 tsp = 4.92892 mL

Milliliters (mL)

—

Result rounded to 4 decimal places

Common conversions

Teaspoons (tsp)	Milliliters (mL)	Common measure

Summary

Convert teaspoons to milliliters instantly — 1 US teaspoon equals exactly 4.92892 mL.

How it works

Enter a volume in teaspoons in the input field.
The converter multiplies the value by 4.92892159375 to get milliliters.
The result updates instantly as you type.
Use the swap button to convert milliliters back to teaspoons.
Copy the result with one click for use elsewhere.

Use cases

Scale a recipe that lists ingredients in teaspoons for a metric kitchen.
Measure liquid medicine doses when the syringe is marked in mL.
Convert small ingredient amounts when following an international recipe.
Verify the volume of a teaspoon when calibrating measuring spoons.
Convert flavoring extracts or essential oils from tsp to mL for cosmetic formulas.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu