Direct answer: Convert millimeters to inches by dividing by 25.4; convert inches to millimeters by multiplying by 25.4. Enter a trimmer setting below to convert units. The result is a mathematical conversion, not a promise about the cut length or guard fit.
Convert a beard-trimmer length
Enter the length printed on your trimmer or in its manual. This tool runs in your browser and does not send or save your input.
3 mm = 0.118 in.
Quick reference
| Setting in mm | Approximate inches |
|---|---|
| 0.5 | 0.020 |
| 1 | 0.039 |
| 2 | 0.079 |
| 3 | 0.118 |
| 6 | 0.236 |
| 10 | 0.394 |
| 20 | 0.787 |
The calculation only converts units. A dial setting, guard label, blade exposure, and the hair left after trimming are different things. Manufacturer instructions and the exact model take priority. For example, the Panasonic ER2201/ER2211 manual lists its own 1–20 mm settings and notes that actual cut length can be longer than the selected length.
Choose a length without overcutting
- Find the exact model and the setting printed in its manual.
- Start longer than your target and test a small, low-visibility area.
- Reduce by one setting at a time; do not assume another brand uses the same guard number.
- Use the beard length chart for style descriptions and the guard-size guide for attachment differences.
Frequently asked questions
How many millimeters are in an inch?
One inch equals exactly 25.4 millimeters. Divide millimeters by 25.4 to get inches.
Does 3 mm on one trimmer leave the same hair length as 3 mm on another?
Not necessarily. Comb shape, blade position, hair direction, and model design affect the result. Check the exact manual and test longer first.
Does a guard number convert directly to millimeters?
No universal mapping exists across brands. Use the guard chart supplied for your exact trimmer or clipper.
Primary reference: Panasonic ER2201/ER2211 operating instructions.