Convert mm to thou (thousandths of an inch, also called mils) or thou to mm, with decimal inches, the nearest 1/64 inch and micrometers also shown.

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mm To Thousandths Formula

The calculator’s primary conversion uses thousandths of an inch (thou or mils). The metric relationship below is a separate conversion to thousandths of a millimeter (micrometers, μm), also shown among the results.

μm = mm × 1000

Variables:

  • μm is the measurement in micrometers (thousandths of a millimeter)
  • mm is the measurement in millimeters

To convert from millimeters to micrometers, multiply the measurement in millimeters by 1000.

If by “thousandths” you mean thousandths of an inch (thou/mil), use the exact conversion below (since 1 in = 25.4 mm):

thou = (mm) / (25.4) × 1000
Millimeters to Micrometers Conversion Table (1 mm = 1000 µm)
Millimeters (mm) Micrometers (µm)
0.10100
0.20200
0.25250
0.30300
0.50500
0.75750
11,000
1.51,500
22,000
2.52,500
33,000
44,000
55,000
66,000
88,000
1010,000
1212,000
1515,000
2020,000
2525,000
Micrometers (µm) here are thousandths of a millimeter. Conversion: µm = mm × 1000, mm = µm ÷ 1000.

What is an mm To Thousandths Conversion?

An mm to thousandths conversion means converting a length in millimeters into a unit expressed in thousandths. The exact meaning depends on context: in machining, “thou” (or “mil”) means a thousandth of an inch (0.001 in); in metric work, a thousandth of a millimeter is a micrometer (μm). Also, since 1 mm = 0.001 m, a millimeter is already one thousandth of a meter.