Square Inch to Square Centimetre
Free instant square inch to square centimetre converter. 1 in² = 6.4516 cm².
Common Square Inch to Square Centimetre values
| Square Inch (in²) | Square Centimetre (cm²) |
|---|---|
| 1 | 6.4516 |
| 5 | 32.258 |
| 10 | 64.516 |
| 25 | 161.29 |
| 50 | 322.58 |
| 100 | 645.16 |
| 500 | 3225.8 |
| 1000 | 6451.6 |
How does Square Inch to Square Centimetre conversion work?
Type a value in the Square Inch (in²) field and the equivalent in Square Centimetre (cm²) appears instantly to the right. The math uses the exact formula shown above — no rounding errors, no approximations beyond standard floating-point precision. Use the swap button to flip the units and see the inverse conversion.
Square Inch. About 6.45 square centimetres. Used for screen sizes and small surface areas.
Square Centimetre. One ten-thousandth of a square metre. Common for small surface areas.
⚡ Instant results
No submit button — the result updates as you type. Math runs entirely in your browser, so it’s as fast as your device.
📱 Use on any device
Works in any modern browser — Mac, Windows, Linux, iPhone, Android, tablets. No installation, no signup.
🎯 Accurate conversions
Conversion factors come from the official standard (NIST, BIPM, ISO definitions where applicable). Values are precise to standard floating-point limits.
🎁 Always free, no signup
Free, every time. No account, no email, no “trial” that becomes paid. Ad-supported so you never have to pay.
How it works — the formula
Area scales as length squared.
For any length scale s (metres per unit), area scale = s².
1 ft² = 0.3048² m² = 0.09290304 m² exactly
1 acre = 4,046.8564224 m² exactly (= 1 chain × 1 furlong)Area is a derived unit — the square of length — so any area conversion factor is the square of the corresponding length factor. The acre (4,046.8564224 m²) and hectare (10,000 m² exactly) are both standardized; one acre is also exactly 43,560 ft². Square metre is the SI derived unit.
Worked examples
- Inputs:
- 1,500 ft² = ? m²
- Output:
- 1,500 × 0.09290304 ≈ 139.355 m²
- Inputs:
- 5 acres = ? ha
- Output:
- 5 × 4,046.8564224 / 10,000 ≈ 2.0234 ha
- Inputs:
- (1 ft)² in m²
- Output:
- (0.3048 m)² = 0.0929 m² — squaring confirms the area scale
Limitations
- Land-survey areas may use "US survey foot" rather than international foot — the difference is ~4 ppm, deprecated as of 2023.
- Surface area on a curved manifold (sphere, ellipsoid) requires intrinsic geometry, not the flat conversion factor.
- Floor-area definitions (gross vs net vs rentable) are governed by BOMA / IPMS standards, not unit conversion.
- Pixel-area (digital images) is not a physical area unit — px² depend on display DPI.
Area conversions are exact rational arithmetic for SI ↔ US-customary; trailing-digit differences come from binary floating-point only.