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millimeters → inches

8 millimeters to inches

0.31 in

8 mm = 0.31 in.

inches

0.31in

8 mm = 0.31 in

In short

How many inches is 8 millimeters?

8 mm = 0.31 in. 1 millimeter = 0.039370 inches, so the working is 8 × 0.039370 = 0.31.

The working

The factor below is an exact definition rather than a measurement, so nothing is approximated in the arithmetic. The only rounding on this page happens where a number is displayed.

1 millimeter = 0.039370 inches
8 × 0.039370 = 0.31

How much precision do you need?

Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.

Rounded toAnswer (in)Off by
Whole number0−0.31496
1 decimal0.3−0.01496
2 decimals0.31−0.00496

Round trip: take 0.31 in back the other way and you land on 7.8740 mm — a drift of 0.1260 mm. That gap is the rounding, not the conversion.

Frequently asked questions

What is 8 millimeters in inches?

8 millimeters is 0.31 inches. 1 millimeter = 0.039370 inches, so the working is 8 × 0.039370 = 0.31.

How accurate is 0.31 in?

Rounding to 0.31 in and converting straight back gives 7.8740 mm, a drift of 0.1260 mm from the 8 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.

Nearby values

Any value at all

Mm to Inches Converter

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