Convert Square Centimeter to Square Inch
Convert square centimeters to square inches instantly. 1 square centimeter = 0.15500031 square inch — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Inch to Square Centimeter converter for the reverse conversion.
Units explained
Square Centimeter
A square centimeter is a metric unit of area equal to 10⁻⁴ m² (1 cm × 1 cm). It is widely used in everyday measurement, lab work, and small-area applications.
Derived by squaring the centimeter (1/100 of a meter). The centi- prefix comes from the Latin 'centum' (hundred).
Square centimeters express the cross-sectional area of pipes and cables, the surface area of small everyday objects, biological tissue samples, and many engineering quantities. The SI unit for medical/pharmaceutical dose-per-area is often expressed in cm².
Centimeter has been part of the metric system since 1795.
Square Inch
A square inch is an imperial unit of area equal to exactly 0.00064516 m², the area of a square with sides of one inch. It is widely used in the United States for small-area measurements.
Derived by squaring the inch. The inch was standardized to exactly 25.4 mm via the 1959 International Yard and Pound Agreement.
Square inches are used extensively in US engineering, manufacturing, real estate (for floor plans), and everyday small-area measurements. Engine displacement is often expressed in cubic inches but cross-sections in square inches.
Inch dates to medieval English usage; modern exact value standardized in 1959.
Square Centimeter to Square Inch conversion formula
The relationship between square centimeters and square inches:
To convert square centimeters to square inches, multiply the value in square centimeters by 0.15500031. To reverse, multiply square inches by 6.4516.
How to use this converter
Type a value into the calculator. The result in square inches updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Square Inch to Square Centimeter converter for the reverse direction.
Step-by-step: convert square centimeters to square inches
- Write down the value in square centimeters (cm²).
- Multiply that value by the factor 0.15500031.
- The product is the equivalent value in square inches (in²).
- To reverse, multiply the square inch value by 6.4516.
Worked examples
Example 1 — Convert 1 cm² to in²:
1 × 0.15500031 = 0.15500031 in²
Example 2 — Convert 100 cm² to in²:
100 × 0.15500031 = 15.5000310001 in²
Real-world example — Hair-width scale measurements
A 70-square centimeter measurement (about the diameter of a human hair) is the kind of value materials engineers regularly express in adjacent micro-scale units like square inches for direct comparison across supplier datasheets.
70 cm² × 0.15500031 = 10.8500217 in²
Real-world example — Paper and film thicknesses
At the thickness of office paper (roughly 3 square centimeters), converting between sub-millimeter units is routine for packaging and printing buyers comparing quotes from metric and US suppliers.
3 cm² × 0.15500031 = 0.46500093 in²
Real-world example — Plastic-film thickness alternates
A 150-square centimeter plastic film converts cleanly to square inches — useful for packaging buyers reconciling supplier datasheets across metric and US measurement systems.
150 cm² × 0.15500031 = 23.2500465001 in²
Square Centimeter to Square Inch conversion table
Standard reference values for converting square centimeters to square inches:
| Square Centimeter [cm²] | Square Inch [in²] |
|---|---|
| 0.01 | 0.0015500031 |
| 0.1 | 0.015500031 |
| 1 | 0.15500031 |
| 2 | 0.31000062 |
| 3 | 0.46500093 |
| 4 | 0.62000124 |
| 5 | 0.77500155 |
| 10 | 1.5500031 |
| 20 | 3.1000062 |
| 30 | 4.6500093 |
| 40 | 6.2000124 |
| 50 | 7.7500155 |
| 100 | 15.5000310001 |
| 500 | 77.5001550003 |
| 1000 | 155.0003100006 |
Frequently asked questions
How many square inches is 1 square centimeter?
How do I convert square centimeters to square inches?
How do I convert square inches back to square centimeters?
How many square inches is 100 square centimeters?
Popular area unit conversions
Convert Square Centimeter to other area units
Show all Square Centimeter conversions
Metric / SI (15 units)
Imperial / US Customary (15 units)
US Survey (5 units)
Indian Subcontinent (16 units)
Other Regional (10 units)
Scientific / Physics (5 units)
Sources & references
Conversion factor (1 cm² = 0.15500031 in²) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.