Micrometers Ra to microinches Ra
Type a value in µm Ra to get it in µin Ra instantly.
62.99µin Ra
That's about the same as a machined surface. A human hair is about 43.75 times that height.
Convert the other way: µin Ra to µm Ra
What it means
How rough is that?
Ra is an average of the deviations, so two surfaces with the same Ra can feel and wear quite differently. Ra and Rq relate exactly only for a sine profile.
The math
How to convert µm Ra to µin Ra
To convert micrometers Ra to microinches Ra, multiply by 39.3701.
Example: 1.6 µm Ra × 39.3701 = 62.9921 µin Ra.
In the other direction, 1 µin Ra = 0.0254 µm Ra.
Every unit
Your roughness in every unit
Tables
µm Ra to µin Ra conversion table
| µm Ra | µin Ra |
|---|---|
| 0.025 µm Ra | 0.984252 µin Ra |
| 0.05 µm Ra | 1.9685 µin Ra |
| 0.1 µm Ra | 3.93701 µin Ra |
| 0.2 µm Ra | 7.87402 µin Ra |
| 0.4 µm Ra | 15.748 µin Ra |
| 0.8 µm Ra | 31.4961 µin Ra |
| 1.6 µm Ra | 62.9921 µin Ra |
| 3.2 µm Ra | 125.984 µin Ra |
| 6.3 µm Ra | 248.031 µin Ra |
| 12.5 µm Ra | 492.126 µin Ra |
| 25 µm Ra | 984.252 µin Ra |
| 50 µm Ra | 1,968.5 µin Ra |
µin Ra to µm Ra conversion table
| µin Ra | µm Ra |
|---|---|
| 0.025 µin Ra | 0.000635 µm Ra |
| 0.05 µin Ra | 0.00127 µm Ra |
| 0.1 µin Ra | 0.00254 µm Ra |
| 0.2 µin Ra | 0.00508 µm Ra |
| 0.4 µin Ra | 0.01016 µm Ra |
| 0.8 µin Ra | 0.02032 µm Ra |
| 1.6 µin Ra | 0.04064 µm Ra |
| 3.2 µin Ra | 0.08128 µm Ra |
| 6.3 µin Ra | 0.16002 µm Ra |
| 12.5 µin Ra | 0.3175 µm Ra |
| 25 µin Ra | 0.635 µm Ra |
| 50 µin Ra | 1.27 µm Ra |
Quick answers
Quick answers
- How many µin Ra is 1 µm Ra?
- 1 µm Ra is 39.3701 µin Ra.
- How many µin Ra is 10 µm Ra?
- 10 µm Ra is 393.701 µin Ra.
- How many µin Ra is 1.6 µm Ra?
- 1.6 µm Ra is 62.9921 µin Ra.
The units
About these units
Micrometers Ra (µm Ra)
The international standard for average roughness.
Microinches Ra (µin Ra)
The US unit. 63 µin is the common machined finish.
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