Quick answer: 1 US teaspoon equals 4.92892 mL, usually rounded to 4.93 mL. One metric teaspoon equals exactly 5 mL. Use the calculator below to convert any number of teaspoons to milliliters or milliliters back to teaspoons.
Teaspoons to milliliters formula
Both teaspoons and milliliters measure volume, so this conversion does not depend on the ingredient. Multiply US teaspoons by 4.92892 to get milliliters. For a metric teaspoon, multiply by 5.
US formula: mL = teaspoons × 4.92892
Metric formula: mL = teaspoons × 5
Reverse formula: teaspoons = mL ÷ 4.92892
Teaspoons to mL conversion chart
| Teaspoons | US milliliters | Metric milliliters | Common measure |
|---|---|---|---|
| ¼ tsp | 1.23 mL | 1.25 mL | — |
| ½ tsp | 2.46 mL | 2.5 mL | — |
| 1 tsp | 4.93 mL | 5 mL | 1 teaspoon |
| 2 tsp | 9.86 mL | 10 mL | — |
| 3 tsp | 14.79 mL | 15 mL | 1 tablespoon |
| 6 tsp | 29.57 mL | 30 mL | 1 fluid ounce |
| 12 tsp | 59.15 mL | 60 mL | ¼ cup |
| 24 tsp | 118.29 mL | 120 mL | ½ cup |
| 48 tsp | 236.59 mL | 240 mL | 1 US cup |
US teaspoon vs metric teaspoon
A US teaspoon is 4.92892 mL. A metric teaspoon is 5 mL. The difference is only about 1.4%, so it rarely matters in casual cooking. It can matter in precise baking, nutrition, medicine, and recipes that have been scaled up.
Examples
How many mL is 1 teaspoon?
One US teaspoon is 4.93 mL, commonly rounded to 5 mL. One metric teaspoon is exactly 5 mL.
How many mL is 2 teaspoons?
Two US teaspoons equal 9.86 mL, usually rounded to 10 mL. Two metric teaspoons equal exactly 10 mL.
How many mL is ½ teaspoon?
Half a US teaspoon equals 2.46 mL. Half a metric teaspoon equals 2.5 mL.
Frequently asked questions
Is 5 mL the same as 1 teaspoon?
A metric teaspoon is exactly 5 mL. A US teaspoon is very slightly smaller at 4.92892 mL, which is why many recipes round 1 teaspoon to 5 mL.
How many teaspoons are in 30 mL?
Thirty milliliters equal about 6.09 US teaspoons, or exactly 6 metric teaspoons. It is also roughly 1 US fluid ounce.
Does ingredient density affect teaspoons to mL?
No. Teaspoons and milliliters both measure volume. Density matters only when converting a volume measurement to weight, such as grams or ounces.
Related converters
For ingredient weights, use the teaspoons to grams converter. To convert to weight or fluid ounces, use the teaspoons to ounces converter or the teaspoons to fluid ounces converter.