This converter turns teaspoons into cubic inches instantly, using the exact factor 1 teaspoon = 0.30078125 cubic inches. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
The smallest standard kitchen measure, 4.93 millilitres. The volume of a one-inch cube, traditional for US engine displacement.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
teaspoons- The amount you are converting, measured in teaspoons
0.30078125- The exact number of cubic inches in one teaspoon
cubic inches- The converted result
How it works, step by step
- Enter the number of teaspoons you want to convert.
- The value is multiplied by 0.30078125, the exact conversion factor.
- The result is displayed in cubic inches, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 teaspoons
Multiply 5 by 0.30078125. That gives 1.5039 cubic inches. A quick sanity check: one teaspoon is smaller than one cubic inch, so the number should get smaller — and it does.
Converting 72 teaspoons
72 × 0.30078125 = 21.6562 cubic inches. Working backwards, 21.6562 ÷ 0.30078125 returns 72 teaspoons, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many cubic inches are in one teaspoon?
Exactly 0.30078125. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert teaspoons to cubic inches?
Cubic Inches = teaspoons × 0.30078125. To reverse it, divide instead: teaspoons = cubic inches ÷ 0.30078125, which is the same as multiplying by 3.324675325.
Is the teaspoon bigger than the cubic inch?
No. One teaspoon is only 0.300781 of a cubic inch, so the cubic inch is the larger unit.
Why does my answer differ slightly from other teaspoons to cubic-inches converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a teaspoon?
The smallest standard kitchen measure, 4.93 millilitres.
What is a cubic inch?
The volume of a one-inch cube, traditional for US engine displacement.
Teaspoons to cubic inches reference table
| Teaspoons | Cubic Inches |
|---|---|
| 0.5 tsp | 0.150391 in³ |
| 1 tsp | 0.300781 in³ |
| 2 tsp | 0.601562 in³ |
| 3 tsp | 0.902344 in³ |
| 5 tsp | 1.5039 in³ |
| 10 tsp | 3.0078 in³ |
| 15 tsp | 4.5117 in³ |
| 20 tsp | 6.0156 in³ |
| 25 tsp | 7.5195 in³ |
| 50 tsp | 15.0391 in³ |
| 75 tsp | 22.5586 in³ |
| 100 tsp | 30.0781 in³ |
| 250 tsp | 75.1953 in³ |
| 500 tsp | 150.3906 in³ |
| 1000 tsp | 300.7812 in³ |
Exact factor: 1 teaspoon = 0.30078125 cubic inches. Values rounded for display.