# Beta Ratio Filter Efficiency Calculator

Calculate the efficiency of a filter from the beta ratio with this Filter Efficiency Calculator.

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## What is Beta Ratio?

The Beta Ratio is a filter rating on the performance of a filter to trap

particles of a set micron size, or larger.

B_{x} is the Beta Ratio for a filter for trapping particles of "x" microns.

To find the efficiency of a filter from the Beta Ratio:

Efficiency (%) = 100 - (100/Beta Ratio)

Example: The efficiency of a filter with a Beta Ratio (B_{70}) of 1,000:

Efficiency (%) = 100 - (100/1,000)

Calculated out this gives a filter efficiency of 99.90% for trapping

particles of 70 microns, or larger.