Skip to main content

Teaspoons to Milliliters Converter
↔ Convert mL to tsp instead

Common Conversions

tsp mL
0.25 1.232
0.5 2.464
1 4.929
1.5 7.393
2 9.858
3 14.787
4 19.716
5 24.645
6 29.574
8 39.431
10 49.289

Why this conversion matters in chemistry

Take pediatric liquid dosing. A 1-tsp dose of children's diphenhydramine 12.5 mg/5 mL converts to 4.929 mL on the calibrated oral syringe. That's the FDA 2016 OTC labeling guidance rounds to 5 mL on the mL-equivalent label so caregivers do not measure with a kitchen spoon. The ratio of 4.92892 mL per tsp is exact through the US-customary teaspoon definition. The conversion sits at the boundary between tsp-stated household dose instructions and the mL-graduated dosing devices the AAP Committee on Drugs recommends to prevent dosing errors.

Formula

mL = tsp × 4.92892

Worked Examples

1 tsp = 4.929 mL

One teaspoon — the standard pediatric oral-dose anchor.

0.5 tsp = 2.464 mL

Half a teaspoon — about a small reagent or low-dose addition.

3 tsp = 14.787 mL

Three teaspoons — exactly one US tablespoon.

5 tsp = 24.645 mL

About 25 mL — useful for any quick lab estimate.

Frequently Asked Questions

How many mL is a teaspoon?
1 US teaspoon = 4.92892 mL. Pharmaceutical dosing rounds this to 5 mL on the mL-equivalent label, which is what the calibrated oral syringe is graduated to.
Is a teaspoon exactly 5 mL?
No. A US teaspoon is 4.929 mL. The 5 mL figure is the rounded pharmaceutical convention used on dosing devices to keep household-dose math clean.
Why does this conversion show up in chemistry?
Outreach demos, household-product reformulation, and any analytical work that needs to land a tsp-stated recipe on a mL-graduated burette or pipette.
How many teaspoons in a tablespoon?
Three teaspoons make one tablespoon, so 1 tbsp = 3 × 4.929 = 14.787 mL. The factor is exact through the US-customary definition.