Particle Size Conversion Table

A material’s particle size is typically designated in either microns or mesh. Here you will find a useful particle size conversion table that shows micron to mesh conversions for a fast comparison of particle size between these two units. The chart also allows you to compare sieve designations and sieve openings in inches, millimeters, or microns.

Sieve and Mesh Conventions

Large sieve openings (1 in. to 1/4 in.) have been designated by a sieve "mesh" size that corresponds to the size of the opening in inches. Small sieve "mesh" sizes of 3 1/2 to 400 are designated by the number of openings per linear inch in the sieve.

The following convention is used to characterize particle size by mesh designation:

• "+" before the sieve mesh indicates the particles are retained by the sieve;
• "-" before the sieve mesh indicates the particles pass through the sieve;
• typically 90% or more of the particles will lie within the indicated range.

For example, if the particle size of a material is described as -4 +40 mesh, then 90% or more of the material will pass through a 4-mesh sieve (particles smaller than 4.76 mm) and be retained by a 40-mesh sieve (particles larger than 0.420 mm). If a material is described as -40 mesh, then 90% or more of the material will pass through a 40-mesh sieve (particles smaller than 0.420 mm).

Mesh Sieve Products

We offer a variety of mesh screens for cell dissociation and tissue grinding, testing, and particle separation.