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Teaspoons to Milliliters

Convert teaspoon to milliliter instantly — type a value and read the result, with the exact formula shown.

Reviewed by the CalcCafe editorial team · Last updated 1 July 2026 · How we test our tools

Example

1 tsp = 4.928922 mL, 5 tsp = 24.64461 mL, 10 tsp = 49.28922 mL.

Common conversions: teaspoon to milliliter

Quick reference for the tsp → mL values you are most likely to need, computed with the exact factor the converter above uses. It includes the specific values people most often look up (0.5 tsp, 0.25 tsp, 5 tsp, 1 tsp, 2 tsp).

Teaspoon (tsp)Milliliter (mL)
0.25 tsp1.2322 mL
0.5 tsp2.4645 mL
1 tsp4.9289 mL
2 tsp9.8578 mL
3 tsp14.7868 mL
4 tsp19.7157 mL
5 tsp24.6446 mL
10 tsp49.2892 mL
15 tsp73.9338 mL
20 tsp98.5784 mL
25 tsp123.223 mL
30 tsp147.8676 mL
40 tsp197.1569 mL
50 tsp246.4461 mL
60 tsp295.7353 mL
70 tsp345.0245 mL
75 tsp369.6691 mL
80 tsp394.3137 mL
90 tsp443.6029 mL
100 tsp492.8922 mL
150 tsp739.3382 mL
200 tsp985.7843 mL
250 tsp1,232.23 mL
500 tsp2,464.46 mL
1,000 tsp4,928.92 mL

Milliliter to Teaspoon

Milliliter (mL)Teaspoon (tsp)
1 mL0.202884 tsp
5 mL1.0144 tsp
10 mL2.0288 tsp
50 mL10.1442 tsp
100 mL20.2884 tsp

How it works

Milliliter = Teaspoon × 4.928922. Every value is converted through a single liter base unit using internationally defined conversion factors, so any from/to pair stays consistent.

Good to know

Converting teaspoons to milliliters bridges two very different measuring worlds: the spoon you scoop with in an American kitchen and the precise metric markings on a syringe, medicine cup, or European recipe. It comes up most often when you are doubling a recipe written in US units, dosing a child's liquid medication, or following baking instructions from a metric country that lists ingredients in mL rather than spoons.

The teaspoon here is the US customary teaspoon, defined as exactly one-sixth of a US fluid ounce, which works out to 4.928922 mL. The milliliter, by contrast, is pure metric — one-thousandth of a liter — and is the same everywhere in the world. That mismatch in origin is why the number is so awkward: a clean metric unit is being measured against a spoon size that was standardized around the US gallon, not the liter.

For everyday cooking, the rule of thumb is simply to treat 1 tsp as 5 mL. The real value is only about 1.4 percent smaller, so a teaspoon of vanilla or baking powder is close enough at 5 mL that no recipe will notice. To go the other way fast, remember that roughly 3 teaspoons fill 15 mL (one tablespoon), and 20 teaspoons make about 100 mL.

The most common mistake is assuming all teaspoons are 5 mL. They are not: a UK or Australian metric teaspoon is defined as exactly 5 mL, while the US teaspoon on this page is 4.928922 mL. The gap is trivial in the kitchen but matters for liquid medicine, where pharmacists and dosing devices use the exact 5 mL metric spoon — so always dose with a marked oral syringe, never a cutlery teaspoon, which can hold anywhere from 3 to 7 mL.

Frequently asked questions

How do you convert teaspoon to milliliter?
Multiply the number of teaspoons by 4.928922 to get milliliters. For example, 1 tsp = 4.928922 mL.
What is 1 teaspoon in milliliters?
1 teaspoon equals 4.928922 milliliters (1 tsp = 4.928922 mL).
How many teaspoons are in 1 milliliter?
There are 0.2028841 teaspoons in 1 milliliter.
Is this converter free and private?
Yes. It runs entirely in your browser, so your inputs never leave your device, there is no sign-up, and it works offline once loaded.
Are the conversions exact?
Conversions use internationally defined factors and are exact where the definitions are exact (for example, 1 inch = 2.54 cm). Displayed results are rounded for readability.

People also ask

How many mL is 2 teaspoons?
Two US teaspoons equal 9.857844 mL, which rounds to about 10 mL. Using the 5 mL kitchen rule, you can just call it 10 mL.
Is a teaspoon 5 mL or 4.929 mL?
A US customary teaspoon is 4.928922 mL, while the UK and Australian metric teaspoon is defined as exactly 5 mL. Most measuring spoons and medicine dosing follow the rounded 5 mL standard.
How many teaspoons are in 10 mL?
10 mL equals about 2.029 US teaspoons, so just over 2 teaspoons. In metric-spoon terms (5 mL each) it is exactly 2 teaspoons.
How many teaspoons is 15 mL?
15 mL is about 3.043 US teaspoons, essentially 3 teaspoons — which is also one US tablespoon. This is why a tablespoon is often listed as 15 mL.
How much is half a teaspoon in mL?
Half a US teaspoon is 2.464461 mL, commonly rounded to 2.5 mL. Most oral syringes have a 2.5 mL mark for exactly this dose.
Why isn't a teaspoon exactly 5 mL?
The US teaspoon was defined from the US fluid ounce (1/6 of an ounce), which predates metric standardization, giving 4.928922 mL. Metric countries later rounded their cooking teaspoon to a clean 5 mL.
How many mL in a teaspoon of medicine?
For medicine, a teaspoon is treated as exactly 5 mL, since that is the international standard for liquid dosing. Always measure with a marked syringe or cup rather than a kitchen spoon for accuracy.
How do I convert teaspoons to mL without a calculator?
Multiply the number of teaspoons by 5 for a quick estimate (1 tsp is about 5 mL). For the exact US value, multiply by 4.928922 instead.
Is 1 mL equal to 1 tsp?
No, a teaspoon is much bigger than a milliliter: 1 US teaspoon is 4.928922 mL, so 1 mL is only about one fifth of a teaspoon (1 ÷ 4.928922 = 0.203 tsp). Medicine dosing cups and syringes are marked in mL precisely because a kitchen spoon can be off by a lot. If a label says 5 mL, that is one measuring teaspoon, not five.
Is 1 tablespoon 5 mL or 15 mL?
15 mL. A US tablespoon is 3 teaspoons, or 3 × 4.928922 = 14.786766 mL, which recipes and medicine labels round to 15 mL; 5 mL is a teaspoon, not a tablespoon. Keep the two straight, because confusing them triples or thirds the amount.

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Sources & references

These tools follow our methodology and provide educational estimates only — verify important figures with a qualified professional.