AQL sampling calculator (ISO 2859-1 / ANSI Z1.4)
Enter the lot size, the general inspection level and the AQL. You get the sample size code letter, the sample size and the accept (Ac) and reject (Re) numbers for single sampling under normal inspection. Use it to plan a receiving inspection or a sorting check during containment (D3).
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- Code letter
- G
- Sample size
- 50
- Accept (Ac)
- 1
- Reject (Re)
- 2
Letter G has an arrow ↓ at AQL 1.0, so the first plan below it is used: letter H, n = 50.
Inspect 50 items. Accept the lot with 1 or fewer nonconforming; reject with 2 or more.
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How the lookup works
- Table I gives the sample size code letter from the lot size and inspection level (level II is the default).
- Table II-A gives the sample size and Ac/Re for that letter and AQL.
- If the cell has an arrow, follow it to the first plan with Ac/Re and use that plan's sample size (not the original letter's).
- If the sample size is equal to or larger than the lot, inspect 100 %.
- Special inspection levels S-1 to S-4 are not included. Use the standard's Table I if your plan specifies them.
- Ac 0 means the lot is rejected if one nonconforming unit is found in the sample. It does not guarantee a zero-defect lot, and AQL is not the acceptable defect rate of a single lot.
Example: a lot of 280 at level II is letter G (n = 32). At AQL 1.0, G has a down arrow, so the plan below is used: letter H, n = 50, Ac 1, Re 2.
This tool covers single sampling, normal inspection only. It does not apply the switching rules to tightened or reduced inspection. Your customer's sampling agreement always overrides it.
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