Woven Wire Mesh Calculator
Work out aperture size, open area and weight of woven wire mesh in seconds – plus wire gauge, length and stainless grade converters Jump To The CalculatorChoosing the right mesh for your sieve or separator? Use this free calculator to check the aperture, open area and weight of a woven wire mesh from its mesh count and wire diameter, or work backwards from the aperture you need.
You can also convert standard wire gauges (SWG) to wire diameters, switch between feet and metres, add or subtract roll lengths and check the composition of the stainless steel grades we use for meshes and contact parts.
All results are theoretical. If you need a mesh for a William Boulton vibratory separator or a replacement screen for another machine, call our team on 01782 816158 and we will confirm the right specification.
Mesh calculator
Mesh aperture, open area & weight
Enter the mesh count or aperture size and the wire diameter of a square-aperture, plain-weave woven wire mesh.
Weight is calculated with the ISO 9044 empirical formula for steel (12.7 × d² ÷ pitch), adjusted for the density of the material selected. Actual weight can be up to around 3% lower. Results are theoretical; please confirm critical specifications with our team.
Standard wire gauge (SWG) to wire diameter
Convert an imperial standard wire gauge to a wire diameter, or find the nearest SWG for a diameter in millimetres.
Convert feet & inches to metric
Convert lengths in either direction.
Imperial to metric
Metric to imperial
Add or subtract feet & inches
Useful for working out cut lengths from a roll.
Stainless steel grade compositions
Typical chemical composition limits (% by weight) for the AISI grades most used in woven wire mesh. Single figures are maximums.
| Element | % by weight |
|---|---|
| Carbon (C) | – |
| Silicon (Si) | – |
| Manganese (Mn) | – |
| Phosphorus (P) | – |
| Sulphur (S) | – |
| Chromium (Cr) | – |
| Molybdenum (Mo) | – |
| Nickel (Ni) | – |
| Others | – |
Typical limits based on the AISI designations. Exact limits vary slightly between standards (e.g. EN 10088, ASTM A240); refer to the mill certificate supplied with your mesh.
How the calculations work
The calculator uses the standard definitions for square-aperture woven wire cloth set out in ISO 9044, where w is the aperture width, d is the wire diameter and p is the pitch (the distance between the centres of two neighbouring wires), all in millimetres.
- Pitch – p = 25.4 ÷ mesh count per inch (or 10 ÷ mesh count per cm)
- Aperture – w = p − d
- Open area – (w ÷ p)² × 100, the percentage of the screen surface that is open
- Weight – 12.7 × d² ÷ p kg/m² for steel, adjusted for the density of other materials. Actual weight can be up to around 3% lower.
For example, a 100 mesh with 0.1 mm wire has a 0.254 mm pitch, a 0.154 mm (154 micron) aperture, 36.8% open area and weighs around 0.5 kg/m² in stainless steel.
Have a question? Call us on 01782 816158 or:
Woven wire mesh FAQs
What does mesh count mean?
Mesh count is the number of apertures per linear inch of mesh. A 100 mesh has 100 apertures in every 25.4 mm. Because the wire takes up part of each inch, two meshes with the same count but different wire diameters will have different aperture sizes.
Is a higher mesh count finer?
Yes. More apertures per inch means a smaller pitch, so the apertures get smaller as the mesh count goes up.
What is open area and why does it matter?
Open area is the percentage of the mesh surface that is holes rather than wire. A higher open area lets product pass through faster, while a thicker wire with a lower open area gives a stronger, longer-lasting screen. The right balance depends on your product and throughput.
How do I convert microns to mesh?
Select “I know the aperture” in the calculator, enter your aperture in millimetres (1 micron = 0.001 mm) and the wire diameter, and the calculator gives you the matching mesh count.
Which stainless steel grade should I choose?
304 is the general-purpose grade for most screening work. 316 and 316L contain molybdenum for better resistance to chlorides and chemicals, and the low-carbon “L” grades are preferred where mesh is welded. Talk to us if you are unsure which suits your product.
Can you supply replacement meshes for my separator?
Yes. We supply replacement meshes and screens for our own machines and for many other manufacturers’ separators. See our aftercare & spare parts page or get in touch.