AQL Calculator

How to read the result

The inspector draws the number of units shown at random from the packed cartons and checks each one. Defects are counted by type. If the number of major defects is at or below the accept number, and the same for minor defects, that part of the inspection passes. If it reaches the reject number, it fails. Most buyers do not accept any critical defects.

General Inspection Level II is the usual default. Level I uses a smaller sample and is sometimes used for low-risk repeat orders. Level III uses a larger sample for higher-risk goods. The AQL values are the buyer's choice and should be written into the purchase order and the inspection checklist before production.

What the calculator does not do

It covers single sampling plans for normal inspection only. It does not cover tightened or reduced inspection, special inspection levels such as S-1 to S-4, or double sampling. Sample sizes for on-site tests such as drop tests or hi-pot tests are usually set separately and are smaller. For the background, read our guides to AQL sampling, defect classification and on-site tests.