Teaspoons to millilitres

Multiply teaspoons by 4.9289 to get millilitres.

1 tsp = 4.9289 mLNIST HB 44 · BIPM SI

Convert

tsp

9.8578mL

2 tsp = 9.8578 mL

How to convert teaspoons to millilitres

The millilitre is one thousandth of a litre, equal to one cubic centimetre (cm³). The teaspoon is a US teaspoon, one third of a tablespoon (4.92892159375 millilitres).

Worked example — 2 tsp: 2 × 4.9289 = 9.8578 mL.

Teaspoons to millilitres table

Common conversions.
Teaspoons	Millilitres
0.25 tsp	1.2322 mL
0.5 tsp	2.4645 mL
1 tsp	4.9289 mL
1.5 tsp	7.3934 mL
2 tsp	9.8578 mL
3 tsp	14.7868 mL
4 tsp	19.7157 mL
6 tsp	29.5735 mL
8 tsp	39.4314 mL

Reverse and related

mL → cup1 mL = 0.00422675 cup cup → mL1 cup = 236.5882 mL fl oz → mL1 fl oz = 29.5735 mL mL → fl oz1 mL = 0.033814 fl oz tbsp → mL1 tbsp = 14.7868 mL L → mL1 L = 1,000 mL

About teaspoons and millilitres

Teaspoon (tsp)

1 tsp = 4.9289 mL

Definition. A US teaspoon, one third of a tablespoon (4.92892159375 millilitres)

History and origin

The teaspoon was originally the spoon used to stir tea and became standardised as a cooking measure at one third of a tablespoon, about 4.93 millilitres in the US.

Current use

Teaspoons measure small amounts in recipes and are also used, loosely, for medicine doses.

Source: NIST Handbook 44, Appendix C §2 (U.S. Customary Units) and §5 (Tables of Equivalents)

Millilitre (mL)

1 mL = 0.202884 tsp

Definition. One thousandth of a litre, equal to one cubic centimetre (cm³)

History and origin

The millilitre is one thousandth of a litre, equal to one cubic centimetre. It came with the decimal metric system as the unit for small liquid volumes.

Current use

Millilitres are used for recipes, medicine doses and cosmetics, and are printed on most small bottles and cans.

Source: BIPM SI Brochure (2019); the litre is an SI-accepted unit (1 L = 1 dm³)

Where people use this

Teaspoons: recipes, medicine doses. Millilitres: recipes, medicine doses, cosmetics. 1 US teaspoon is about 4.93 mL.

How we know this is right

The factor is fixed by the standards that define the units, not chosen — so it is exact, not a measurement:

1 mL = 0.2028841362 tsp, so 1 tsp = 1 ÷ 0.2028841362 = 4.9289 mL.

Every value is carried to full double precision; the display is rounded.

Sources: BIPM SI Brochure (2019); the litre is an SI-accepted unit (1 L = 1 dm³); NIST Handbook 44, Appendix C §2 (U.S. Customary Units) and §5 (Tables of Equivalents).

Questions people ask

How many mL in a teaspoon?

One US teaspoon is about 4.93 mL.

How many mL is 2 teaspoons?

2 teaspoons is about 9.86 mL.

Is a teaspoon 5 mL?

The US teaspoon is 4.93 mL; recipes often round it to 5 mL.

All teaspoon conversions

Tablespoons to teaspoons1 tbsp = 3 tsp