tsp to mL Converter — Teaspoons to Millilitres
Convert teaspoons to millilitres for US, metric or UK recipes. A US teaspoon is 4.929 mL, a metric teaspoon is exactly 5 mL, and a UK teaspoon is about 5.919 mL — choose the system that matches your recipe to get the accurate volume in mL.
tsp
Measurement system
1 tsp = 4.92892 mL (US customary)
- 1
mL per teaspoon
4.92892 mLUS customary standard. - 2
Total volume
3 × 4.92892 = 14.787
How does this calculator work?
Multiply teaspoons by 4.929 for US mL, by 5 for metric mL, or by 5.919 for UK mL. 3 tsp = 1 tbsp in every system. 1 metric tsp = 5 mL exactly; 1 US tsp ≈ 4.929 mL; 1 UK tsp ≈ 5.919 mL. System choice matters — a UK tsp is about 20% larger than a US tsp.
Formula
How this is calculated
A teaspoon is a cooking-measure unit whose exact volume depends on the measurement system. In the United States, 1 teaspoon = 1/3 US tablespoon = 4.92892159375 mL (derived from the US customary gallon). In Australia, Canada, and most metric countries, the teaspoon is rounded to exactly 5 mL for kitchen convenience. In the UK, 1 teaspoon ≈ 5.91939 mL (1/3 of an Imperial tablespoon of 17.7582 mL). Choosing the wrong system in baking can introduce errors of up to 20% — a UK teaspoon is about 20% larger than a US teaspoon.
This calculator multiplies the number of teaspoons by the teaspoon size (in mL) for the chosen system. It also shows the result in tablespoons (always 3 tsp per tbsp), cups (where the system defines a cup), microlitres and US fluid ounces for reference.
Note that the standard measuring spoon in a given country is calibrated to that country's system. An old UK recipe specifying "1 tsp" uses the Imperial 5.92 mL measure, whereas a modern metric spoon holds exactly 5 mL. When in doubt, metric (5 mL) is the safest universal default.
Frequently asked questions
1 US teaspoon ≈ 4.929 mL. 1 metric teaspoon = 5.000 mL (exact). 1 UK/Imperial teaspoon ≈ 5.919 mL. The answer varies by system — for everyday cooking the difference is negligible, but for precise or scaled recipes always state which system you are using.
In all three measurement systems (US, metric, and UK), 1 tablespoon = 3 teaspoons. The tablespoon itself differs: 1 US tbsp ≈ 14.787 mL, 1 metric tbsp = 15 mL (Australia) or 15 mL (Canada), 1 UK tbsp ≈ 17.758 mL.
Yes, especially for leavening agents like baking powder and baking soda where small quantities make a significant difference. 1 metric tsp of baking powder is 5 mL, but a UK tsp is 18.4% more (5.919 mL). Stick to the same system throughout a recipe, and use calibrated measuring spoons rather than cutlery teaspoons which vary widely in size.
Also known as
TG we-Calculate Editorial Team. (2026). tsp to mL Converter — Teaspoons to Millilitres [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/tsp-ml-converter
TG we-Calculate Editorial Team. "tsp to mL Converter — Teaspoons to Millilitres." TG we-Calculate. 2026. https://we-calculate.com/calculator/tsp-ml-converter.
TG we-Calculate Editorial Team, "tsp to mL Converter — Teaspoons to Millilitres," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/tsp-ml-converter
@misc{wecalculate_tsp_ml_converter, title = {tsp to mL Converter — Teaspoons to Millilitres}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/tsp-ml-converter}}, year = {2026}, note = {TG we-Calculate} }
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