Length · Unit Converter

Convert Square Thou to Square Centimeter

Convert square thous to square centimeters instantly. 1 square thou = 6.4516e-6 square centimeter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Centimeter to Square Thou converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Length category 2 min read Published Last reviewed Updated

Units explained

Imperial / US Customary

Square Thou

What is a square thou?

A square thou is an imperial unit of area equal to 6.4516×10⁻¹⁰ m², identical to the square mil. The word 'thou' is short for 'thousandth' (of an inch).

Origin of the square thou

Identical in value to the square mil; 'thou' is the British engineering term, 'mil' is the American term. Both refer to 1/1000 of an inch.

Where it is used

Square thous are used in British and Commonwealth engineering contexts where 'thou' is preferred over 'mil', particularly in mechanical engineering tolerance specifications.

When and where it was developed

Standardized via the 1959 International Yard and Pound Agreement.

Metric / SI

Square Centimeter

What is a 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.

Origin of the square centimeter

Derived by squaring the centimeter (1/100 of a meter). The centi- prefix comes from the Latin 'centum' (hundred).

Where it is used

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.

When and where it was developed

Centimeter has been part of the metric system since 1795.

Square Thou to Square Centimeter conversion formula

The relationship between square thous and square centimeters:

1 thou² = 6.4516e-6 cm²
1 cm² = 155000.31000062 thou²

To convert square thous to square centimeters, multiply the value in square thous by 6.4516e-6. To reverse, multiply square centimeters by 155000.31000062.

How to use this converter

Type a value into the calculator. The result in square centimeters 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 Centimeter to Square Thou converter for the reverse direction.

Step-by-step: convert square thous to square centimeters

  1. Write down the value in square thous (thou²).
  2. Multiply that value by the factor 6.4516e-6.
  3. The product is the equivalent value in square centimeters (cm²).
  4. To reverse, multiply the square centimeter value by 155000.31000062.

Worked examples

Example 1 — Convert 1 thou² to cm²:
1 × 6.4516e-6 = 6.4516e-6 cm²

Example 2 — Convert 100 thou² to cm²:
100 × 6.4516e-6 = 0.00064516 cm²

Real-world example — Spanning sub-micron to micron scale

Crossing from square thous to square centimeters is the everyday workflow of microscopy and semiconductor engineering — a measurement of 1000 square thous translates to a much more compact value in square centimeters that fits the scale of biological cells and process nodes.

1000 thou² × 6.4516e-6 = 0.0064516 cm²

Real-world example — Sub-visible-light wavelength

500 square thous (the green-yellow visible band) equals 0.5 square centimeters — the canonical conversion in optics between wavelength specifications and micron-scale lens-coating thicknesses.

500 thou² × 6.4516e-6 = 0.0032258 cm²

Square Thou to Square Centimeter conversion table

Standard reference values for converting square thous to square centimeters:

Square Thou [thou²]Square Centimeter [cm²]
0.016.4516e-8
0.16.4516e-7
16.4516e-6
21.29032e-5
31.93548e-5
42.58064e-5
53.2258e-5
106.4516e-5
200.000129032
300.000193548
400.000258064
500.00032258
1000.00064516
5000.0032258
10000.0064516

Frequently asked questions

How many square centimeters is 1 square thou?
1 square thou equals 6.4516e-6 square centimeter.
How do I convert square thous to square centimeters?
Multiply the value in square thous by 6.4516e-6 to get square centimeters.
How do I convert square centimeters back to square thous?
Multiply the value in square centimeters by 155000.31000062, or use the Square Centimeter to Square Thou converter.
How many square centimeters is 100 square thous?
100 square thous equals 0.00064516 square centimeters, because 100 × 6.4516e-6 = 0.00064516.

Convert Square Thou to other area units

Show all Square Thou conversions

Sources & references

Conversion factor (1 thou² = 6.4516e-6 cm²) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.