Mesh to Micron Converter

Mesh to micron conversion turns a sieve mesh number into the real opening size in microns (µm). DigiCalc's mesh to micron converter does this instantly, in both directions. You can move between mesh count, microns, millimetres and inches without a printed chart. Knowing the exact micron opening behind each mesh number removes the guesswork.

This guide covers how to convert mesh to micron in full. It includes the complete mesh size chart and mesh size table, with mesh, microns, mm and inches. It also covers the reverse micron to mesh direction. Dedicated sections break down the most searched sizes, such as 100, 200, 325 and 400 mesh.

What Is Mesh Size?

Mesh size is the number of openings in a sieve or screen across one linear inch. A 100 mesh screen has 100 openings per inch. A 20 mesh screen has 20. A higher mesh number means smaller openings and finer filtration. A lower mesh number means larger openings and coarser separation.

Mesh is a counting unit, not a direct length. Two screens with the same mesh number can have different openings. This happens when their wire diameter differs. Standardised sieve series like ASTM E11 fix both the mesh count and the exact aperture. Mesh particle size describes the largest particle that can pass through a screen.

What Is a Micron?

A micron, written µm, is one millionth of a metre. It is also called a micrometre. One micron equals 1,000 nm, or one thousandth of a millimetre. It is the standard unit for stating a sieve opening and a particle size. For scale, a human hair is roughly 70 microns across.

Microns give an absolute, unambiguous measurement. Mesh is relative to wire spacing. This is exactly why mesh to micron conversion matters. It translates a relative count into a precise opening. You can then compare openings across standards and suppliers.

Mesh vs Micron: Key Differences

Mesh and micron describe the same screen from opposite directions. Mesh counts openings per inch. Micron measures the size of one opening. As the mesh number goes up, the micron value goes down. The table below summarises this mesh and micron chart relationship.

How to Convert Mesh Size to Micron

A fast estimate for mesh size to micron conversion divides 25,400 by the mesh number. The figure 25,400 is the number of microns in one inch.

Microns ≈ 25,400 ÷ mesh number

For example, 25,400 ÷ 60 gives about 423 microns. This formula is only a rough guide. It ignores wire thickness, so it overstates the opening on fine screens. Real wire takes up part of each inch, so the true opening is smaller. For accurate work, use the standardised ASTM E11 values in the chart below. According to the NIST Office of Weights and Measures, traceable opening sizes keep sieve measurements consistent between laboratories.

Wire Mesh Gauge Chart and Wire Diameter

The opening behind a mesh number depends on wire thickness as well as wire count. Each inch is shared between the openings and the wires that frame them. A wire mesh gauge chart lists the wire diameter for each mesh grade. A wire mesh size chart pairs that diameter with the resulting aperture. Thicker wire on the same mesh count leaves a smaller opening, which is exactly why two screens labelled 100 mesh can differ.

Each pitch equals 25,400 divided by the mesh number, and that pitch splits into the opening plus one wire. So the wire diameter is simply the pitch minus the opening. Reading wire diameter alongside the opening explains the gap between the quick formula and the real value. The estimate assumes zero wire thickness, so it always runs high. A micron mesh screen or micron mesh filter rated by its opening already accounts for the wire. This is why standardised charts beat the formula for any precise work.

Mesh Size Chart and Mesh Size Table (Mesh, Microns, MM, Inches)

This mesh size chart lists the US Standard sieve sizes from ASTM E11. Each ASTM mesh size has one fixed opening. Use it as a mesh and micron chart, a screen mesh size chart, or a sieve size chart. The mesh opening size, or mesh sieve size, is the gap between the wires. Find your mesh number in the first column. Then read across for microns, millimetres and inches. This mesh micron conversion table is the most accurate quick reference here.

The same mesh micron conversion chart works as a filter mesh size chart. It suits screens, strainers and filtration media. Each row gives the largest particle, in microns, that the screen lets through. Bookmark it as your mesh conversion chart and mesh micron chart. It doubles as a mesh size to micron chart one way, and a micron to mesh chart the other.

Mesh to MM Conversion and Mesh Size in MM

To express mesh size in mm instead of microns, divide the micron value by 1,000. One millimetre equals 1,000 microns. For mesh to mm conversion, 100 mesh at 150 microns becomes 0.150 mm. And 20 mesh at 850 microns becomes 0.850 mm. The millimetre column above lists every standard sieve. So it doubles as a full set of standard sieve sizes in mm. This mesh size conversion works both ways. Use the mesh mm conversion table below for the common grades.

Micron to Mesh: Reverse Conversion

To convert micron to mesh, find the micron value in the chart. Then read back to the mesh number. You can also estimate with mesh ≈ 25,400 ÷ microns. This micron to mesh conversion helps when a spec is in microns. Standard sieves come in fixed steps. Pick the closest available mesh rather than an exact match.

Use this micron to mesh chart alongside DigiCalc's converter above. You can then move in whichever direction your project needs. It is the quickest way to convert mesh to micron and back.

100 Mesh to Micron

100 mesh equals 150 microns (0.150 mm) on the ASTM E11 standard sieve scale. A 100 mesh screen has 100 openings per inch. It blocks particles larger than about 150 microns. It is a common grade for coarse powders, granular products and pre-filtration.

200 Mesh to Micron

200 mesh equals 75 microns (0.075 mm). A 200 mesh screen has 200 openings per inch. It separates fine powders and stops particles above roughly 75 microns. It is widely used for pigments, fine flour, cosmetics and many pharmaceutical powders.

325 Mesh to Micron

325 mesh equals 45 microns (0.045 mm), so mesh 325 in micron terms gives a screen opening of 45 microns. A 325 mesh screen has 325 openings per inch. It is often the boundary where charts state sizes in microns, not mesh. It suits very fine powders such as metal powders, ceramics and high grade pigments. Fine 325 mesh sieves are usually woven from stainless steel mesh for durability and corrosion resistance.

400 Mesh to Micron

400 mesh equals 38 microns (0.038 mm). It is one of the finest standard sieves in regular use, with 400 openings per inch. A 400 mesh screen suits ultra fine powders, advanced ceramics and electronics materials. It also suits precision filtration below 40 microns.

20 Mesh to MM

20 mesh equals 0.850 mm (850 microns). A 20 mesh screen has 20 openings per inch. It is a coarse grade for sand, granules, coffee and seeds. In inches the opening is about 0.0331 inch. This makes 20 mesh a popular general purpose size.

100 Mesh to MM

100 mesh equals 0.150 mm (150 microns). In millimetres, the opening is just over a tenth of a millimetre. It handles fine granular material while passing easily for most powders. The grades below show how fast the opening shrinks as mesh rises.

50 Micron Mesh

A 50 micron mesh sits between 270 mesh (53 microns) and 325 mesh (45 microns). So the closest standard screen is about 270 to 300 mesh. 50 micron screens are common in paint strainers, liquid filtration and food processing. They remove fine grit while letting liquid pass freely.

50 Micron Screen

A 50 micron screen filters down to 0.050 mm, sitting between 270 mesh (53 microns) and 325 mesh (45 microns). The nearest standard grade is about 270 to 300 mesh. A 50 micron screen is a common paint strainer and liquid filtration grade. It removes fine grit and undissolved solids while keeping a high flow rate. No standard mesh lands exactly on 50 microns. Suppliers often quote these screens in microns rather than a mesh number. So the micron value is the safer specification for fine filtration.

100 Micron Mesh

A 100 micron mesh matches roughly 140 to 150 mesh. The chart lists 140 mesh at 106 microns. 100 micron filtration is a popular general purpose grade. It suits water filters, hydroponics, and removing visible sediment while keeping flow rate high.

25 Micron Mesh

A 25 micron mesh matches about 500 mesh on the standard scale. This is a fine filtration grade. It serves paints, inks, fuels and pharmaceutical liquids. It captures particles too small to see. It still works as a cleanable screen, not a disposable depth filter.

Common Applications of Mesh to Micron Conversion

Mesh to micron conversion is used wherever particle size must match a screen. In filtration, the micron rating sets the largest particle that passes. So a 200 mesh (75 micron) screen and a 75 micron filter do the same job. In food processing, mesh grades sort flour, sugar and spices. In mining, sieve analysis reports particle size distribution by mesh.

Manufacturing and coatings rely on it too. Suppliers specify powder coatings, pigments and metal powders in microns but apply them through mesh screens. Laboratories use ASTM E11 sieves to run particle size tests. The same chart links their mesh stack to the micron results they report.

Mesh to Micron Conversion Examples

A few worked examples show how the conversion behaves across the range:

• A coffee grinder set for 30 mesh gives particles around 600 microns (0.600 mm), a medium grind.
• A 200 mesh painters screen blocks anything larger than 75 microns.
• A 325 mesh sieve in a ceramics lab passes only powder finer than 45 microns.
• A 500 mesh screen, at 25 microns, removes particles about one third the width of a human hair.
• A 20 mesh garden sieve, at 0.850 mm, screens stones and clumps out of soil.
• A 50 mesh kitchen strainer, near 300 microns, holds back tea leaves and pulp.

Each example follows the same rule. The micron opening sets the cut point. Everything larger stays behind. Reading the mesh number as its micron value predicts what a screen will pass. This is the practical value of a reliable mesh to micron conversion.

Mesh Sizes by Industry

The same mesh to micron chart is read differently in each field. Each industry cares about one particular size band. Seeing where common mesh numbers land helps you sanity check a conversion.

In food and beverage, bakers sift flour through about 100 mesh (150 microns). Powdered sugar sits near 200 mesh (75 microns). Filter coffee falls around 30 mesh (600 microns). In agriculture, seed and soil screening uses 10 to 40 mesh. That covers roughly 2 mm down to 0.425 mm.

In paints and coatings, strainers in the 50 to 200 micron range catch lumps before spraying. That matches about 80 mesh down to 200 mesh. In pharmaceuticals, active powders are often controlled at 200 to 325 mesh. That keeps dissolution and blending consistent.

In mining and metal powders, finishing grades push to 400 and 500 mesh. There the openings drop to 38 and 25 microns. The principle stays the same everywhere. Pick the mesh whose micron opening just exceeds your largest particle. Then confirm the value against a standard chart.

Why Sieve Size Accuracy Matters in Quality Control

In quality control, a sieve is a measuring instrument, not just a strainer. Saying a powder is finer than 75 microns only means something if the test sieve is accurate. The 200 mesh screen used must truly open to 75 microns. This is why laboratories buy certified sieves. They also recheck them over time, because wires stretch and openings widen.

Correct conversion also prevents costly mismatches between teams. Purchasing may order screens by mesh. Engineering may write the spec in microns. A single conversion error can let oversized particles through a whole production run. One agreed chart, tied to ASTM E11, keeps everyone on the same opening size.

How Mesh, Micron and Particle Size Relate

A mesh rating is effectively a cut point. It tells you the largest particle that can pass. A 100 mesh screen, at 150 microns, holds back anything wider than 150 microns. So mesh particle size and micron opening are treated as the same number. One counts wires, the other measures a gap.

Real powders are never a single size. They hold a distribution of particles. Sieve analysis sorts that distribution with a stack of screens. The stack runs from coarse at the top to fine at the bottom. The amount caught on each screen is reported against its micron opening. That builds a particle size curve. Engineers then quote a median size, where 50% of the material is finer.

Particle shape matters too. The opening size assumes a roughly round particle. Long or flat particles can slip through a smaller opening. A sieve sorts by width, not by total length. Knowing this keeps mesh to micron conversion realistic.

US Standard, Tyler and ISO Mesh Standards

Three main systems define sieve openings, and they do not line up perfectly. The US Standard series is defined in ASTM E11. It is the most common in North America. It is also the basis for the mesh size table on this page. The Tyler series is similar but uses different reference points. So a Tyler 100 mesh and a US 100 mesh are close, not identical.

The ISO 565 and ISO 3310 series describe sieves by aperture directly. They use millimetres and microns rather than a mesh count. This avoids ambiguity entirely. A chart saying 200 mesh equals 75 microns follows the US Standard. A Tyler chart may list 74 microns for a near equivalent. The gaps are small but real. Always note which standard a supplier uses.

For reference, a US Standard sieve size chart and a US standard sieve sizes table both come from ASTM E11. So a US mesh size chart matches the values on this page. A Tyler mesh size chart uses its own numbering, and ISO charts list the aperture directly, giving a clean sieve size to micron reading. When you only have an opening, a micron to mesh conversion chart points you back to the nearest mesh number in each system. The same openings form a strainer mesh size chart, so a kitchen or industrial strainer blocks the same particles as the matching sieve grade.

How to Choose the Right Mesh Size

Picking a mesh size balances fineness against flow. Follow these steps:

1. Identify the smallest particle you must keep out, in microns.
2. Use the chart above to find the mesh that matches that micron value.
3. Check flow: finer mesh filters more but clogs faster.
4. Allow a margin, since worn screens open up over time.

As a quick guide, coarse work like gravel or coffee uses 8 to 30 mesh. General purpose powder work sits around 40 to 100 mesh. Fine powders, pigments and precision filtration fall in the 200 to 500 mesh range. Matching the mesh to the job avoids both under filtering and over filtering.

Mesh to Micron in Filtration and Micron Ratings

In filtration, the micron value behind a mesh number is the screen's rating. It is the size above which particles are blocked. A 75 micron screen and a 200 mesh screen remove the same particles. This is why mesh to micron conversion is so useful. A filter may be sold by one unit and a screen by the other.

There is a difference between a sieve rating and a filter micron rating. Sieve openings are an absolute, measured gap. Filter media ratings can be absolute or nominal. Absolute means almost no particle above the rating passes. Nominal means most but not all are caught. So confirm whether a micron figure is an absolute opening or a nominal rating.

Limitations of Mesh to Micron Conversion

Mesh to micron values are not perfectly fixed. The same mesh number can give a slightly different opening. It depends on the wire diameter. So two suppliers labelling a screen 100 mesh may differ. The quick 25,400 ÷ mesh formula is only an estimate. It drifts further from reality as mesh gets finer.

Standards also differ slightly. US Standard (ASTM E11), Tyler and ISO 565 do not use the same steps. So always confirm which standard a chart follows. For critical work, rely on a calibrated, traceable sieve. Treat this chart as a reliable reference, not a certification.

Related DigiCalc Converters

For the unit conversions behind these openings, use DigiCalc's tools. The millimeter to micrometer converter moves between mm and microns directly. The cm to inches converter helps with length work. For every length unit in one place, use DigiCalc's length converter. You can also browse every tool on the DigiCalc converters page.