Convert Micrometers to Inches
1 micrometer is 0.00003937 in. One micrometer is exactly 0.0000393700787402 inches.
One micrometer is 3.9370 × 10^-5 inches. To convert micrometers to inches, multiply by 3.9370 × 10^-5; to go the other way, divide by 3.9370 × 10^-5 or multiply by 25400. The relation is exact but the figure is not: it is a rounding of a number that does not terminate, and it follows from NIST. A millionth of a meter, still widely called a micron.
Factor checked against the defining standard · How we check
- Micrometers × 3.9370 × 10^-5
1 * 0.00003940 in
1 micrometer in every length unit
| Unit | Value | Exact factor |
|---|---|---|
| inches | 0.00003937007874 in | × 0.0000393700787402 |
| feet | 0.000003280839895 ft | × 0.00000328083989501 |
| yards | 0.000001093613298 yd | × 0.00000109361329834 |
| miles | 0.0000000006213711922 mi | × 0.000000000621371192237 |
| millimeters | 0.001 mm | × 0.001 |
| decimetres | 0.00001 dm | × 0.00001 |
| centimeters | 0.0001 cm | × 0.0001 |
| meters | 0.000001 m | × 0.000001 |
| kilometers | 0.000000001 km | × 0.000000001 |
| nautical miles | 0.0000000005399568035 nmi | × 0.000000000539956803456 |
| micrometers (as entered) | 1 µm | — |
| nanometers | 1,000 nm | × 1,000 |
| thou | 0.03937007874 thou | × 0.0393700787402 |
Factors are entered by hand from NIST rather than derived from a units library, so the ones that terminate are exact rather than rounded.
The same converter answers this pair however it is written: micrometres to inches is the British spelling of the same units — the metre and the litre are spelled that way outside the United States and the quantity does not change.
How do you convert micrometers to inches? The converter and the working
- 1.Take the measurement in micrometers.
- 2.Multiply by 3.9370 × 10^-5 — that is how many inches fit in one micrometer.
- 3.To go back the other way, divide by 3.9370 × 10^-5, or multiply by 25400.
Worked example: 25 micrometers to inches
- Formula
- µm × 3.9370 × 10^-5 = in
- Arithmetic
- 25 × 3.9370 × 10^-5 = 0.0009843 in
- Answer
- 25 µm = 0.0009843 in
The factor is rounded for display; the figure above is computed from the full value.
Micrometers to inches conversion table
| Micrometers | Inches |
|---|---|
| 1 µm | 0.00003937 in |
| 2 µm | 0.00007874 in |
| 3 µm | 0.0001181 in |
| 4 µm | 0.0001575 in |
| 5 µm | 0.0001969 in |
| 6 µm | 0.0002362 in |
| 7 µm | 0.0002756 in |
| 8 µm | 0.000315 in |
| 9 µm | 0.0003543 in |
| 10 µm | 0.0003937 in |
| 12 µm | 0.0004724 in |
| 15 µm | 0.0005906 in |
| 20 µm | 0.0007874 in |
| 25 µm | 0.0009843 in |
| 50 µm | 0.001969 in |
| 100 µm | 0.003937 in |
| 200 µm | 0.01 in |
| 300 µm | 0.01 in |
| 500 µm | 0.02 in |
| 1000 µm | 0.04 in |
| 2000 µm | 0.08 in |
| 5000 µm | 0.2 in |
| 10000 µm | 0.39 in |
What is a micrometer?
A millionth of a meter, still widely called a micron. Machining tolerances, filter ratings and cell diameters are all quoted here.
What is an inch?
Exactly 25.4 millimeters since the 1959 international yard and pound agreement, and one twelfth of a foot.
How many inches are in a micrometer?
One micrometer is 3.9370 × 10^-5 inches. Going the other way, one inch is 25400 micrometers. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every length unit here
The whole group — 13 units with their symbols and the size of each one in meters — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a micrometer.
Source: NIST — international yard and pound agreement (inch = 25.4 mm exactly)
Cite this page
- APA
- Rule Calculator. (2026). Convert Micrometers to inches. Rule Calculator. https://rulecalculators.com/convert/micrometer-to-inch
- MLA
- "Convert Micrometers to inches." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/micrometer-to-inch.
- Chicago
- Rule Calculator. "Convert Micrometers to inches." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/micrometer-to-inch.
The date is when the figures on this page were last checked against their source, not the day you opened it. Add your own access date if your style needs one.
Questions people actually ask
- How many inches are in a micrometer?
- 3.9370 × 10^-5. Exactly 25.4 millimeters since the 1959 international yard and pound agreement, and one twelfth of a foot.
- How do I convert inches back to micrometers?
- Divide by 3.9370 × 10^-5, or multiply by 25400 — they are the same operation.
Other length conversions
Inches to micrometers — the same conversion the other way.