Length · Unit Converter

Convert Mil to Centimeter

Convert mils to centimeters instantly. 1 mil = 0.00254 centimeter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Centimeter to Mil 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

Mil

What is a mil?

A mil (also called a thou) is an Imperial unit of length equal to one thousandth of an inch (1/1000 in = 0.0254 mm = 25.4 μm exactly). It is used in engineering, manufacturing, and materials specifications.

Origin of the mil

The mil is derived from the Latin mille, "thousand," denoting one-thousandth of an inch. Standardized in industrial use during the 19th-century rise of precision engineering.

Where it is used

Mils are used to specify thicknesses of plastic films, foils, paper, copper traces on printed circuit boards (PCBs), wire insulation, and paint coatings. A standard sheet of paper is about 4 mils thick.

When and where it was developed

Adopted in 19th-century engineering practice; the value (1/1000 in) became exact in 1959 when the inch was fixed at 25.4 mm via the International Yard and Pound Agreement. The British term is "thou"; American term is "mil".

Metric / SI

Centimeter

What is a centimeter?

A centimeter is a metric unit of length equal to one hundredth of a meter (1/100 m). It is one of the most commonly used SI sub-units in daily life, especially for measuring small objects, body dimensions, paper sizes, and short distances.

Origin of the centimeter

The centimeter emerged from the French metric system established by the French Academy of Sciences in 1793. The metric system introduced decimal-based prefixes (milli-, centi-, deci-, deca-, hecto-, kilo-) to create proportional sub-units of the meter.

Where it is used

Centimeters are the standard unit for everyday measurement in nearly every country outside the United States. They are used for body height, clothing sizes, rainfall, paper formats (A4 is 21 × 29.7 cm), screen dimensions, and most consumer product specifications.

When and where it was developed

Developed in France during the late 18th century as part of the metric system designed by the French Academy of Sciences. Formally adopted in France in 1795 and ratified internationally through the Metre Convention signed in Paris in 1875.

Mil to Centimeter conversion formula

The relationship between mils and centimeters:

1 mil = 0.00254 cm
1 cm = 393.7007874016 mil

To convert mils to centimeters, multiply the value in mils by 0.00254. To reverse, multiply centimeters by 393.7007874016.

How to use this converter

Type a value into the calculator. The result in 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 Centimeter to Mil converter for the reverse direction.

Step-by-step: convert mils to centimeters

  1. Write down the value in mils (mil).
  2. Multiply that value by the factor 0.00254.
  3. The product is the equivalent value in centimeters (cm).
  4. To reverse, multiply the centimeter value by 393.7007874016.

Worked examples

Example 1 — Convert 1 mil to cm:
1 × 0.00254 = 0.00254 cm

Example 2 — Convert 100 mil to cm:
100 × 0.00254 = 0.254 cm

Real-world example — Packaging gauge

A 4-mil plastic bag thickness is a common spec for grocery and freezer bags. Converting from mils to centimeters is what packaging buyers do whenever they bridge US and metric supplier quotes.

4 mil × 0.00254 = 0.01016 cm

Real-world example — Plastic film and laminate thickness

A 500-mil sheet is a typical spec for ID-card laminates and film overlays. Converting to centimeters aligns the value with the unit most CAD systems and material datasheets prefer.

500 mil × 0.00254 = 1.27 cm

Mil to Centimeter conversion table

Standard reference values for converting mils to centimeters:

Mil [mil]Centimeter [cm]
0.012.54e-5
0.10.000254
10.00254
20.00508
30.00762
40.01016
50.0127
100.0254
200.0508
300.0762
400.1016
500.127
1000.254
5001.27
10002.54

Frequently asked questions

How many centimeters is 1 mil?
1 mil equals 0.00254 centimeter.
How do I convert mils to centimeters?
Multiply the value in mils by 0.00254 to get centimeters.
How do I convert centimeters back to mils?
Multiply the value in centimeters by 393.7007874016, or use the Centimeter to Mil converter.
How many centimeters is 100 mils?
100 mils equals 0.254 centimeters, because 100 × 0.00254 = 0.254.

Convert Mil to other length units

Show all Mil conversions

Sources & references

Conversion factor (1 mil = 0.00254 cm) verified against the following authoritative sources:

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