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Length converter

Calculate, convert and check circuit values in your browser.

Inputs

Results

nm
1 nm
µm
0.001 µm
mm
0.000001 mm
cm
0.0000001 cm
m
0.000000001 m
km
0.000000000001 km
mil
0.00003937007874 mil
in
0.00000003937007874 in
ft
0.000000003280839895 ft
yd
0.000000001093613298 yd
mi
0.0000000000006213711922 mi

Questions, examples and engineering limits

Convert metric and imperial lengths, including PCB mils and inches. Check exact conversion factors, examples and the difference between mil and millimetre.

Content updated:

How is Length Converter: mm, Inches, Mils, Feet and Metres calculated?

Use 1 in = 25.4 mm; 1 mil = 0.001 in. Convert metric and imperial lengths, including PCB mils and inches. Check exact conversion factors, examples and the difference between mil and millimetre.

Sources: nist.gov [1]

How do I calculate this example: 10 mil?

0.254 mm. This is a calculated example under the model stated above; it is not a measured component specification.

Which units does Length Converter: mm, Inches, Mils, Feet and Metres use?

nm, µm, mm, cm, m, km, mil, in, ft, yd, mi. Convert prefixes before substituting values; keep the input and output units attached to every number.

Sources: nist.gov [1]

Is mil the same as millimetre?

No. One mil is 0.0254 mm. Confusing mil with mm introduces a factor of about 39.37 in PCB dimensions.

Sources: nist.gov [1]

Is 1 inch exactly 25.4 mm?

Yes, for the international inch. This exact definition does not make a measured dimension or its tolerance exact.

Sources: nist.gov [1]

Should I round before entering PCB dimensions?

Keep enough digits during calculation and round the final result to fabrication resolution. Converting units does not check manufacturing capability.

Sources: nist.gov [1]

Answers use the stated model and units. Examples are calculated values, not measurements or component ratings.