Thickness converter

Mils to mm Converter

Convert mil thickness to millimeters, inches, microns, and thou. Handy for plastic sheeting, films, liners, tape, labels, and small workshop measurements.

Convert thickness

Enter a thickness in mils, mm, inches, or microns. Results update instantly.

Main conversion 6 mil = 0.1524 mm

Common medium plastic sheeting thickness.

Inches 0.006 in
Microns 152.4 µm

6 mil equals 0.1524 mm, 0.006 inch, and 152.4 microns.

Roll area helper

Estimate square feet and square meters from a rectangular sheet or roll.

1,000 sq ft About 92.9 square meters.

Mil thickness formula

A mil is one thousandth of an inch. To convert mils to millimeters, multiply by 0.0254.

  • mm = mils × 0.0254
  • mils = mm ÷ 0.0254
  • microns = mils × 25.4

Where mils are used

Mils are common for plastic sheeting, vapor barriers, greenhouse film, pond liners, trash bags, tape, laminating film, and coatings. The word can also mean milliradians in optics, but this page is for thickness.

For product specs, compare both thickness and material type. Two sheets with the same mil rating can feel different if the plastic, reinforcement, or coating is different.

Common mil to mm chart

MilsMillimetersInchesMicronsCommon note

Mils to mm FAQ

How thick is 10 mil in mm?

10 mil is 0.254 mm, 0.010 inch, or 254 microns.

How thick is 20 mil in mm?

20 mil is 0.508 mm, 0.020 inch, or 508 microns.

Is 4 mil or 6 mil plastic thicker?

6 mil plastic is thicker. 4 mil is 0.1016 mm, while 6 mil is 0.1524 mm.