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Convert Thou to Centimeters

1 thou is 0.00254 cm. One thou is exactly 0.00254 centimeters.

One thou is 0.00254 centimeters. To convert thou to centimeters, multiply by 0.00254; to go the other way, divide by 0.00254 or multiply by 393.70079. The factor is exact rather than rounded: it follows from NIST.

Factor checked against the defining standard · How we check

Centimeters
0.00254 cm
Thou × 0.00254
1 * 0.002540.003 cm

1 thou in every length unit

1 thou expressed in every length unit
UnitValueExact factor
inches0.001 in× 0.001
feet0.00008333333333 ft× 0.0000833333333333
yards0.00002777777778 yd× 0.0000277777777778
miles0.00000001578282828 mi× 0.0000000157828282828
millimeters0.0254 mm× 0.0254
decimetres0.000254 dm× 0.000254
centimeters0.00254 cm× 0.00254
meters0.0000254 m× 0.0000254
kilometers0.0000000254 km× 0.0000000254
nautical miles0.00000001371490281 nmi× 0.0000000137149028078
micrometers25.4 µm× 25.4
nanometers25,400 nm× 25,400
thou (as entered)1 thou—

Factors are entered by hand from NIST rather than derived from a units library, so the ones that terminate are exact rather than rounded.

The same converter answers this pair however it is written: thou to centimetres is the British spelling of the same units — the metre and the litre are spelled that way outside the United States and the quantity does not change.

How do you convert thou to centimeters? The converter and the working

  1. 1.Take the measurement in thou.
  2. 2.Multiply by 0.00254 — that is how many centimeters fit in one thou.
  3. 3.To go back the other way, divide by 0.00254, or multiply by 393.70079.

Worked example: 25 thou to centimeters

Formula
thou × 0.00254 = cm
Arithmetic
25 × 0.00254 = 0.06 cm
Answer
25 thou = 0.06 cm

The factor is exact, so this figure is exact too — only the display is rounded.

Thou to centimeters conversion table

Thou to centimeters conversion table
ThouCentimeters
1 thou0.00254 cm
2 thou0.01 cm
3 thou0.01 cm
4 thou0.01 cm
5 thou0.01 cm
6 thou0.02 cm
7 thou0.02 cm
8 thou0.02 cm
9 thou0.02 cm
10 thou0.03 cm
12 thou0.03 cm
15 thou0.04 cm
20 thou0.05 cm
25 thou0.06 cm
50 thou0.13 cm
100 thou0.25 cm
200 thou0.51 cm
300 thou0.76 cm
500 thou1.27 cm
1000 thou2.54 cm
2000 thou5.08 cm
5000 thou12.7 cm
10000 thou25.4 cm

What is a thou?

A thousandth of an inch, exactly 25.4 micrometers, and called a mil in American workshops — the same word the metric world uses for a millimeter, which is why a drawing marked "5 mil" is worth checking twice.

What is a centimeter?

One hundredth of a meter, and the unit most of the world states height in.

How many centimeters are in a thou?

One thou is 0.00254 centimeters, exactly. Going the other way, one centimeter is 393.70079 thou. 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 length unit here

The whole group — 13 units with their symbols and the size of each one in meters — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a thou.

Source: NIST — international yard and pound agreement (inch = 25.4 mm exactly)

Cite this page

APA
Rule Calculator. (2026). Convert Thou to centimeters. Rule Calculator. https://rulecalculators.com/convert/thou-to-centimeter
MLA
"Convert Thou to centimeters." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/thou-to-centimeter.
Chicago
Rule Calculator. "Convert Thou to centimeters." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/thou-to-centimeter.

The date is when the figures on this page were last checked against their source, not the day you opened it. Add your own access date if your style needs one.

Questions people actually ask

How many centimeters are in a thou?
0.00254. One hundredth of a meter, and the unit most of the world states height in.
How do I convert centimeters back to thou?
Divide by 0.00254, or multiply by 393.70079 — they are the same operation.

Other length conversions

Centimeters to thou — the same conversion the other way.

Calculators that work in length