1 millimeters to inches
0.04 in
1 mm = 0.04 in.
inches
0.04in
1 mm = 0.04 in
In short
How many inches is 1 millimeters?
1 mm = 0.04 in. 1 millimeter = 0.039370 inches, so the working is 1 × 0.039370 = 0.04.
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 1 × 0.039370 = 0.04
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 to | Answer (in) | Off by |
|---|---|---|
| Whole number | 0 | −0.03937 |
| 1 decimal | 0.0 | −0.03937 |
| 2 decimals | 0.04 | +0.00063 |
Round trip: take 0.04 in back the other way and you land on 1.0160 mm — a drift of 0.0160 mm. That gap is the rounding, not the conversion.
Frequently asked questions
What is 1 millimeters in inches?
1 millimeters is 0.04 inches. 1 millimeter = 0.039370 inches, so the working is 1 × 0.039370 = 0.04.
How accurate is 0.04 in?
Rounding to 0.04 in and converting straight back gives 1.0160 mm, a drift of 0.0160 mm from the 1 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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