Mesh ↔ Micron Conversion
"Mesh" means openings per linear inch. Filter and filtration specs are usually given in microns — convert between them here.
Used for exact opening. Leave as-is for the standard sieve approximation.
Opening: —
= —
= —
ASTM E11 Standard Sieve Series (nominal)
| Mesh | Nominal opening (µm) | ≈ mm |
|---|---|---|
| 4 | 4750 | 4.75 |
| 6 | 3350 | 3.35 |
| 8 | 2360 | 2.36 |
| 10 | 2000 | 2.00 |
| 12 | 1700 | 1.70 |
| 14 | 1400 | 1.40 |
| 16 | 1180 | 1.18 |
| 18 | 1000 | 1.00 |
| 20 | 850 | 0.850 |
| 25 | 710 | 0.710 |
| 30 | 600 | 0.600 |
| 35 | 500 | 0.500 |
| 40 | 425 | 0.425 |
| 45 | 355 | 0.355 |
| 50 | 300 | 0.300 |
| 60 | 250 | 0.250 |
| 70 | 212 | 0.212 |
| 80 | 180 | 0.180 |
| 100 | 150 | 0.150 |
| 120 | 125 | 0.125 |
| 140 | 106 | 0.106 |
| 170 | 90 | 0.090 |
| 200 | 75 | 0.075 |
| 230 | 63 | 0.063 |
| 270 | 53 | 0.053 |
| 325 | 45 | 0.045 |
| 400 | 38 | 0.038 |
Nominal values from ASTM E11 / ISO 565. Actual opening depends on wire diameter: opening = 25.4/mesh − wire dia (mm).