Convert Cubic inches to Cubic millimetres
1 cubic inch is 16,387.06 mm³. One cubic inch is exactly 16387.064 cubic millimetres.
One cubic inch is 16387.064 cubic millimetres. To convert cubic inches to cubic millimetres, multiply by 16387.064; to go the other way, divide by 16387.064 or multiply by 6.1024 × 10^-5. The factor is exact rather than rounded: it follows from NIST Handbook 130. Exactly 16.387064 millilitres, since the inch is exactly 25.4 mm.
Factor checked against the defining standard · How we check
- Cubic inches × 16387.064
1 * 16387.06416,387.064 mm³
1 cubic inch in every volume unit
| Unit | Value | Exact factor |
|---|---|---|
| US teaspoons | 3.324675325 tsp | × 3.32467532468 |
| US tablespoons | 1.108225108 tbsp | × 1.10822510823 |
| US fluid ounces | 0.5541125541 fl oz | × 0.554112554113 |
| US cups | 0.06926406926 cup | × 0.0692640692641 |
| US pints | 0.03463203463 pt | × 0.034632034632 |
| US quarts | 0.01731601732 qt | × 0.017316017316 |
| US gallons | 0.004329004329 gal | × 0.004329004329 |
| milliliters | 16.387064 ml | × 16.387064 |
| liters | 0.016387064 L | × 0.016387064 |
| imperial gallons | 0.00360465015 gal (UK) | × 0.00360465014991 |
| imperial quarts | 0.0144186006 qt (UK) | × 0.0144186005996 |
| imperial pints | 0.0288372012 pt (UK) | × 0.0288372011993 |
| imperial fluid ounces | 0.576744024 fl oz (UK) | × 0.576744023985 |
| imperial gills | 0.1153488048 gi (UK) | × 0.115348804797 |
| cubic millimetres | 16,387.064 mm³ | × 16,387.064 |
| cubic centimetres | 16.387064 cm³ | × 16.387064 |
| cubic inches (as entered) | 1 in³ | — |
| cubic feet | 0.0005787037037 ft³ | × 0.000578703703704 |
| cubic yards | 0.00002143347051 yd³ | × 0.0000214334705075 |
| cubic metres | 0.000016387064 m³ | × 0.000016387064 |
Factors are entered by hand from NIST Handbook 130 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert cubic inches to cubic millimetres? The converter and the working
- 1.Take the measurement in cubic inches.
- 2.Multiply by 16387.064 — that is how many cubic millimetres fit in one cubic inch.
- 3.To go back the other way, divide by 16387.064, or multiply by 6.1024 × 10^-5.
Worked example: 25 cubic inches to cubic millimetres
- Formula
- in³ × 16387.064 = mm³
- Arithmetic
- 25 × 16387.064 = 409,676.6 mm³
- Answer
- 25 in³ = 409,676.6 mm³
The factor is exact, so this figure is exact too — only the display is rounded.
Cubic inches to cubic millimetres conversion table
| Cubic inches | Cubic millimetres |
|---|---|
| 1 in³ | 16,387.06 mm³ |
| 2 in³ | 32,774.13 mm³ |
| 3 in³ | 49,161.19 mm³ |
| 4 in³ | 65,548.26 mm³ |
| 5 in³ | 81,935.32 mm³ |
| 6 in³ | 98,322.38 mm³ |
| 7 in³ | 114,709.45 mm³ |
| 8 in³ | 131,096.51 mm³ |
| 9 in³ | 147,483.58 mm³ |
| 10 in³ | 163,870.64 mm³ |
| 12 in³ | 196,644.77 mm³ |
| 15 in³ | 245,805.96 mm³ |
| 20 in³ | 327,741.28 mm³ |
| 25 in³ | 409,676.6 mm³ |
| 50 in³ | 819,353.2 mm³ |
| 100 in³ | 1,638,706.4 mm³ |
| 200 in³ | 3,277,412.8 mm³ |
| 300 in³ | 4,916,119.2 mm³ |
| 500 in³ | 8,193,532 mm³ |
| 1000 in³ | 16,387,064 mm³ |
| 2000 in³ | 32,774,128 mm³ |
| 5000 in³ | 81,935,320 mm³ |
| 10000 in³ | 163,870,640 mm³ |
What is a cubic inch?
Exactly 16.387064 millilitres, since the inch is exactly 25.4 mm. American engine displacement was quoted in it until the 1980s — a 350 small block is 5.7 litres.
What is a cubic millimetre?
A millionth of a litre, because the millimetre is a thousandth of a metre and volume cubes the factor. A microlitre by another name, and the unit injection-moulding shot sizes are quoted in.
How many cubic millimetres are in a cubic inch?
One cubic inch is 16387.064 cubic millimetres, exactly. Going the other way, one cubic millimetre is 6.1024 × 10^-5 cubic inches. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every volume unit here
The whole group — 20 units with their symbols and the size of each one in liters — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a cubic inch.
Cite this page
- APA
- Rule Calculator. (2026). Convert Cubic inches to cubic millimetres. Rule Calculator. https://rulecalculators.com/convert/cubic-inch-to-cubic-millimeter
- MLA
- "Convert Cubic inches to cubic millimetres." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/cubic-inch-to-cubic-millimeter.
- Chicago
- Rule Calculator. "Convert Cubic inches to cubic millimetres." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/cubic-inch-to-cubic-millimeter.
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Questions people actually ask
- How many cubic millimetres are in a cubic inch?
- 16387.064. A millionth of a litre, because the millimetre is a thousandth of a metre and volume cubes the factor. A microlitre by another name, and the unit injection-moulding shot sizes are quoted in.
- How do I convert cubic millimetres back to cubic inches?
- Divide by 16387.064, or multiply by 6.1024 × 10^-5 — they are the same operation.
Other volume conversions
Cubic millimetres to cubic inches — the same conversion the other way.