Mesh Converter
US mesh ↔ Tyler ↔ µm/mm, strictly by the published tables.
Calculator
ASTM E11 × Tyler reference table
56 of 56 sieves| Designation | Alternative (USA) | Aperture (µm) | Tyler mesh | ISO 565 | Wire (mm) |
|---|---|---|---|---|---|
| 125 mm | 5 in. | 125,000 | — | R20/3 | 8 |
| 106 mm | 4.24 in. | 106,000 | — | R40/3 | 6.3 |
| 100 mm | 4 in. | 100,000 | — | — | 6.3 |
| 90 mm | 3 1/2 in. | 90,000 | — | R20/3 | 6.3 |
| 75 mm | 3 in. | 75,000 | — | R40/3 | 6.3 |
| 63 mm | 2 1/2 in. | 63,000 | — | R20/3 | 5.6 |
| 53 mm | 2.12 in. | 53,000 | — | R40/3 | 5 |
| 50 mm | 2 in. | 50,000 | — | — | 5 |
| 45 mm | 1 3/4 in. | 45,000 | — | R20/3 | 4.5 |
| 37.5 mm | 1 1/2 in. | 37,500 | — | R40/3 | 4.5 |
| 31.5 mm | 1 1/4 in. | 31,500 | — | R20/3 | 4 |
| 26.5 mm | 1.06 in. | 26,500 | — | R40/3 | 3.55 |
| 25.0 mm | 1.00 in. | 25,000 | — | — | 3.55 |
| 22.4 mm | 7/8 in. | 22,400 | — | R20/3 | 3.55 |
| 19.0 mm | 3/4 in. | 19,000 | — | R40/3 | 3.15 |
| 16.0 mm | 5/8 in. | 16,000 | — | R20/3 | 3.15 |
| 13.2 mm | 0.530 in. | 13,200 | — | R40/3 | 2.8 |
| 12.5 mm | 1/2 in. | 12,500 | — | — | 2.5 |
| 11.2 mm | 7/16 in. | 11,200 | — | R20/3 | 2.5 |
| 9.5 mm | 3/8 in. | 9,500 | — | R40/3 | 2.24 |
| 8.0 mm | 5/16 in. | 8,000 | — | R20/3 | 2 |
| 6.7 mm | 0.265 in. | 6,700 | — | R40/3 | 1.8 |
| 6.3 mm | 1/4 in. | 6,300 | — | — | 1.8 |
| 5.6 mm | No. 3 1/2 | 5,600 | 3.5 | R20/3 | 1.6 |
| 4.75 mm | No. 4 | 4,750 | 4 | R40/3 | 1.6 |
| 4.00 mm | No. 5 | 4,000 | 5 | R20/3 | 1.4 |
| 3.35 mm | No. 6 | 3,350 | 6 | R40/3 | 1.25 |
| 2.80 mm | No. 7 | 2,800 | 7 | R20/3 | 1.12 |
| 2.36 mm | No. 8 | 2,360 | 8 | R40/3 | 1 |
| 2.00 mm | No. 10 | 2,000 | 9 | R20/3 | 0.9 |
| 1.7 mm | No. 12 | 1,700 | 10 | R40/3 | 0.8 |
| 1.4 mm | No. 14 | 1,400 | 12 | R20/3 | 0.71 |
| 1.18 mm | No. 16 | 1,180 | 14 | R40/3 | 0.63 |
| 1.00 mm | No. 18 | 1,000 | 16 | R20/3 | 0.56 |
| 850 µm | No. 20 | 850 | 20 | R40/3 | 0.5 |
| 710 µm | No. 25 | 710 | 24 | R20/3 | 0.45 |
| 600 µm | No. 30 | 600 | 28 | R40/3 | 0.4 |
| 500 µm | No. 35 | 500 | 32 | R20/3 | 0.315 |
| 425 µm | No. 40 | 425 | 35 | R40/3 | 0.28 |
| 355 µm | No. 45 | 355 | 42 | R20/3 | 0.224 |
| 300 µm | No. 50 | 300 | 48 | R40/3 | 0.2 |
| 250 µm | No. 60 | 250 | 60 | R20/3 | 0.16 |
| 212 µm | No. 70 | 212 | 65 | R40/3 | 0.14 |
| 180 µm | No. 80 | 180 | 80 | R20/3 | 0.125 |
| 150 µm | No. 100 | 150 | 100 | R40/3 | 0.1 |
| 125 µm | No. 120 | 125 | 115 | R20/3 | 0.09 |
| 106 µm | No. 140 | 106 | 150 | R40/3 | 0.071 |
| 90 µm | No. 170 | 90 | 170 | R20/3 | 0.063 |
| 75 µm | No. 200 | 75 | 200 | R40/3 | 0.05 |
| 63 µm | No. 230 | 63 | 250 | R20/3 | 0.045 |
| 53 µm | No. 270 | 53 | 270 | R40/3 | 0.036 |
| 45 µm | No. 325 | 45 | 325 | R20/3 | 0.032 |
| 38 µm | No. 400 | 38 | 400 | R40/3 | 0.03 |
| 32 µm | No. 450 | 32 | — | — | 0.028 |
| 25 µm | No. 500 | 25 | — | — | 0.025 |
| 20 µm | No. 635 | 20 | — | — | 0.02 |
Theory & method
A test sieve is identified by its nominal aperture — the opening w between adjacent wires — not by an arithmetic formula. "Mesh" counts openings per linear inch, so the same mesh number yields different apertures depending on wire diameter. That is why serious converters never use approximations like 25 400/mesh: the only correct source is the published table of the standard.
This converter uses the apertures of ASTM E11 Table 1 (harmonized with ISO 565 / ISO 3310-1) and treats the historical Tyler series as a secondary equivalence via the W.S. Tyler chart. Conversions always route through the aperture in micrometers, and inputs that do not exist in a standard series return the nearest normative neighbors instead of an invented value.
How to use
- 01Choose the input standard (US mesh, Tyler mesh, millimeters or micrometers) and enter the value.
- 02Read the equivalents in every other standard, each traced to its published table.
- 03If the input is not a normative designation, use the suggested neighboring sieves — apertures between designations do not exist physically.
Frequently asked questions
Why does US mesh 100 equal 150 µm and not 254 µm?
25 400/mesh gives the pitch of the weave (aperture + wire diameter), not the opening. ASTM E11 Table 1 defines the aperture of a No. 100 sieve as 150 µm once the wire is accounted for.
Are US and Tyler mesh the same thing?
No. They are distinct historical series. Some numbers coincide (20, 60, 80, 100, 170, 200, 270, 325, 400), but others differ — US 50 corresponds to Tyler 48, and US 10 to Tyler 9.
What if my mesh number is not in the table?
Then there is no such standard sieve. The converter shows the nearest normative designations instead of interpolating, because apertures only exist at the designations defined by the standard.
Normative references
- ASTM E11-95 — Standard Specification for Wire Cloth and Sieves for Testing Purposes, Table 1
- ISO 565:1990 — Test sieves — Metal wire cloth — Nominal sizes of openings
- ISO 3310-1:2016 — Test sieves — Technical requirements and testing — Part 1
- W.S. Tyler — ASTM Sieve Chart and Tyler Equivalents