This is a common question that many people have when measuring small amounts of liquid for cooking, baking, or science experiments. The short answer is no, 1 mL is not exactly half a teaspoon. However, they are close enough in volume that they can be useful conversions.
What is a milliliter?
A milliliter (mL) is a metric unit of volume. 1 mL is equal to one cubic centimeter (cc). There are 1000 mL in 1 liter. Milliliters are commonly used for measuring small amounts of liquids in science, medicine, and cooking.
What is a teaspoon?
A teaspoon is an imperial and US customary unit of volume. In the US, 1 teaspoon is equal to 4.93 mL. So a US teaspoon is just under 5 mL. There are 3 teaspoons in 1 tablespoon and 48 teaspoons in 1 cup.
Teaspoons are commonly used in cooking and baking recipes in the US and some other countries. They provide a convenient way to measure small amounts of liquids like water, oil, extracts, etc.
The volume difference
Since 1 mL equals 1 cc, and a US teaspoon is 4.93 mL, this means that 1 mL is not exactly half a teaspoon. Half of 4.93 mL would be 2.465 mL. So while they are close, 1 mL comes up a bit short of being half a teaspoon.
Here are some key volume comparisons:
- 1 mL = 0.338 US teaspoons
- 1 mL = 0.203 US tablespoons
- 1 teaspoon = 1.033 mL
- 1 tablespoon = 14.787 mL
| Unit | Volume |
|---|---|
| 1 mL | 1 cubic centimeter (cc) |
| 1 teaspoon (US) | 4.93 mL |
| 1 tablespoon (US) | 14.787 mL |
When can they be substituted?
While 1 mL is not exactly half a teaspoon, in some cases they can be substituted in recipes or measurements with little impact:
- When measuring very small amounts of a liquid ingredient – Using 1 mL instead of half a teaspoon will add only a tiny bit more of the ingredient.
- When making a recipe that calls for “a dash” or “a pinch” – 1 mL or half a teaspoon would be nearly indistinguishable.
- When the small variation in volume doesn’t need to be highly precise – In some cooking/baking scenarios, a little more or less liquid won’t make a dramatic difference.
However, there are also scenarios where substituting 1 mL for half a teaspoon is not recommended:
- Baking recipes where getting the right volume and ratios is critical – Baking is more of a science and precise measurements matter.
- Medicine dosing – With medicines you need to strictly follow dosage instructions.
- Chemical experiments – Variations in volumes of chemicals mixed together could alter experimental results.
Converting between mL and teaspoons
Since 1 mL does not equal half a teaspoon, here are some key conversions to remember:
- 1 teaspoon = 4.93 mL
- 2 teaspoons = 9.86 mL
- 1 tablespoon = 14.787 mL
- 1 fluid ounce = 29.57 mL
- 1 cup = 236.59 mL
To convert:
- Teaspoons to mL: Multiply teaspoons by 4.93
- mL to teaspoons: Divide mL by 4.93
- Tablespoons to mL: Multiply tablespoons by 14.787
- mL to tablespoons: Divide mL by 14.787
So for example:
- 5 teaspoons x 4.93 = 24.65 mL
- 15 mL / 4.93 = 3.04 teaspoons
Comparing volumes visually
It can also be helpful to see a visual comparison of 1 mL vs. half a teaspoon. Here’s a look at 1 mL of water versus half a teaspoon of water side by side:
This helps illustrate that while they are very close in volume, 1 mL is slightly less than half a teaspoon. The 1 mL is a touch less deep and narrower than the half teaspoon.
When precision matters
While they are close enough for estimation in some cases, there are many instances where precision matters. Getting the exact intended volumes correct can make a big difference in outcomes.
Some examples where the small difference between 1 mL and half a teaspoon does matter:
- Medicine dosing – Taking 1 mL instead of half a teaspoon could mean nearly a 50% increase in dosage taken. Too high of a medicine dose could cause harm.
- Chemical concentrations – Diluting chemicals changes concentration. Even slightly higher or lower volumes will alter the concentrations of solutions.
- Recipes with yeast – Yeast reacts to the ratio of liquid to dry ingredients. More or less liquid can drastically change how the dough rises.
When working in fields like health, science, or precision cooking, it becomes very important to measure as accurately as possible. Using the right equipment designed for that specific unit of volume can help eliminate errors.
Equipment designed for specific volumes
To accurately measure mL or teaspoons, it’s best to use equipment designed and calibrated specifically for that unit:
- Measuring spoons – Best for measuring teaspoons and tablespoons. Common sets include 1⁄4, 1⁄2, and 1 teaspoon sizes.
- Liquid measuring cups – Designed for measuring cups and ounces. May also have milliliter markings.
- Graduated cylinders – Laboratory tools calibrated for highly accurate milliliter measurements.
- Pipettes and burettes – For precise measurement and transfer of milliliter volumes of liquids.
Any equipment should be periodically checked for accuracy. But using the right tools for the units you need helps remove some of the guesswork and approximations between teaspoons and milliliters.
Converting in recipes and instructions
When following a recipe that uses teaspoons or tablespoons but you only have milliliter tools (or vice versa), you can use the below conversions:
- 1 teaspoon = 4.93 mL
- 1 tablespoon = 14.787 mL
- 2 tablespoons = 29.573 mL
- 1 fluid ounce = 29.573 mL
- 1 cup = 236.588 mL
Some tips for converting:
- Be as precise as possible – Use decimal places for more accuracy.
- Round judiciously – If rounding, be careful not to skew volumes too high or low.
- Check your math – Double check your unit conversions with a calculator.
To go from teaspoons/tablespoons to milliliters – multiply by the conversion factor above. For example:
If a recipe calls for 2 tablespoons (30 mL) of oil, multiply by 14.787:
2 tablespoons x 14.787 = 29.574 mL
To go from milliliters to teaspoons/tablespoons – divide by the conversion factor. For example:
If you need to measure 25 mL of water with teaspoons:
25 mL / 4.93 = 5.07 teaspoons
So you would measure out 5 teaspoons plus a bit extra to reach 25 mL.
Metric conversion charts
You can also use a metric conversion chart or calculator to convert volumes. Here is a quick reference metric conversion chart for volumes:
| US Customary | Metric |
|---|---|
| 1 teaspoon | 4.93 mL |
| 1 tablespoon | 14.79 mL |
| 1 fluid ounce | 29.57 mL |
| 1 cup | 236.59 mL |
| 1 pint | 473.18 mL |
| 1 quart | 946.36 mL |
| 1 gallon | 3,785.41 mL |
Key takeaways
- 1 mL equals 1 cubic centimeter (cc) volume.
- A US teaspoon is 4.93 mL volume.
- So 1 mL is NOT exactly half a teaspoon – it is a bit smaller.
- They can substitute for small volume approximations but not for precision measurements.
- Use measuring tools designed specifically for the units needed – don’t estimate between mL and teaspoons.
- Refer to conversions and charts to calculate between milliliters and teaspoons/tablespoons.
The bottom line
While similar, 1 mL and half a teaspoon are not equal volumes. When precision matters, you cannot substitute one for the other. But for approximations of very small amounts in non-critical applications, they can be useful conversions. Just remember that 1 mL is a touch smaller than half a teaspoon at 4.93 mL versus 5 mL.
