120 millimeters to inches
4.72 in
120 mm = 4.72 in.
inches
4.72in
120 mm = 4.72 in
In short
How many inches is 120 millimeters?
120 mm = 4.72 in. 1 millimeter = 0.039370 inches, so the working is 120 × 0.039370 = 4.72.
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 120 × 0.039370 = 4.72
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 | 5 | +0.27559 |
| 1 decimal | 4.7 | −0.02441 |
| 2 decimals | 4.72 | −0.00441 |
Round trip: take 4.72 in back the other way and you land on 119.8880 mm — a drift of 0.1120 mm. That gap is the rounding, not the conversion.
What 120 mm looks like
120 mm
A compact disc is 120 mm across under the Red Book specification, standardised as IEC 60908.
Frequently asked questions
What is 120 millimeters in inches?
120 millimeters is 4.72 inches. 1 millimeter = 0.039370 inches, so the working is 120 × 0.039370 = 4.72.
How accurate is 4.72 in?
Rounding to 4.72 in and converting straight back gives 119.8880 mm, a drift of 0.1120 mm from the 120 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
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