Volume · Conversion

Convert teaspoon (US) to milliliter.

To convert teaspoon (US) to milliliter, multiply the value by 4.92892. For example, 1 tsp-us = 4.92892 mL.

tsp-us to mL — formula, reference values, and a live converter.

tsp-us = mL

Formula & quick reference

To convert teaspoon (US) to milliliter, multiply the volume value by 4.92892. Teaspoon (US) (tsp-us) and milliliter (mL) both measure volume, and this fixed ratio lets you move between them precisely. Use the formula and reference grid below to check volume figures in engineering specifications, technical drawings, datasheets, and everyday calculations.

Conversion rule: Value × 4.92892 = Result

Worked example: 10 tsp-us × 4.92892 = 49.2892 mL

tsp-us (teaspoon (US))FactormL (milliliter)
1 tsp-us× 4.928924.92892 mL
10 tsp-us× 4.9289249.2892 mL
50 tsp-us× 4.92892246.446 mL
100 tsp-us× 4.92892492.892 mL

Convert teaspoon (US) (tsp-us) to milliliter (mL). This is a fixed-ratio conversion — multiply the input by the factor below.

Formula

mL = tsp-us × 4.92892

Reference values

tsp-us (teaspoon (US))mL (milliliter)
1 tsp-us4.9289 mL
2 tsp-us9.8578 mL
5 tsp-us24.645 mL
10 tsp-us49.289 mL
25 tsp-us123.22 mL
50 tsp-us246.45 mL
100 tsp-us492.89 mL
500 tsp-us2464.5 mL
1000 tsp-us4928.9 mL

Things to watch for

What is a US teaspoon?

One US teaspoon equals exactly one-third of a US tablespoon or about 4.93 milliliters. American cooking recipes and small-dose liquid medications.

What is a milliliter?

One milliliter equals exactly one cubic centimeter (1 ml = 1 cm³) or one-thousandth of a liter. Liquid medicine dosing, recipe ingredients, and laboratory measurement.

How big is one tsp in real terms?

Concrete examples often help when a unit doesn't have an intuitive feel. 1 tsp is roughly the volume of one sugar cube; 3 tsp is one tablespoon.

How to convert US teaspoon to milliliter

To convert a value from US teaspoon (tsp (US)) to milliliter (ml), apply the conversion factor shown in the formula above. The calculation is the same whether you do it by hand, in a spreadsheet, or with the live converter on this page.

Steps:

  1. Take your input value in tsp (US).
  2. Apply the formula mL = tsp-us × 4.92892.
  3. The result is your value in ml.

For repeated calculations, save the formula in a spreadsheet or use the live converter at the top of this page — it handles the math automatically and displays the result as you type.

Frequently asked questions

How do I convert tsp (US) to ml?

Apply the formula tsp (US) → ml shown above, or just type your value into the converter at the top of this page. The result updates instantly.

Which is bigger, tsp (US) or ml?

This depends on the conversion ratio in the formula. If the factor multiplied by your value gives a larger number, then ml is the smaller unit (so it takes more of them to express the same quantity). If the result is smaller, then ml is the larger unit.

When would I use tsp (US) versus ml?

Both units measure volume, so the choice depends on context. Us teaspoon is typically used for cooking, beverages, fuel, and industrial fluid handling; milliliter similarly. Most professional fields standardize on one or the other based on regional conventions or technical tradition.

How precise is this tsp (US) to ml conversion?

The conversion factor shown is the internationally defined exact value (or the best-published approximation if the relationship is irrational, like degrees-to-radians). The live converter on this page uses double-precision floating-point math, accurate to about 15 significant digits — far beyond any practical engineering need.

Is the conversion ratio exact, or an approximation?

Most unit conversions between SI metric units, and between SI and US customary units, have been formally defined as exact values since the 1959 international yard-pound agreement and subsequent SI redefinitions. Exceptions are unit pairs that involve irrational numbers (radians, e.g.) or empirical conversions (like food calories, which depend on temperature). When in doubt, consult the formula at the top of this page.

Related conversions

See also