AQL Chart

AQL 1.0 and 1.5: sample sizes and accept/reject numbers by lot size

Sources checked

Find your lot size in the first column, then read across to your inspection level. Each cell gives the sample size to inspect, followed by Ac and Re in brackets. The code letter comes from Table I, but the arrows in Table II-A can move the plan to another letter, so the same lot and level can show different sample sizes at AQL 1.0 and AQL 1.5.

AQL 1.0 at general inspection levels I, II and III

Lot size Level I Level II Level III
2 to 8 13 (0/1) 13 (0/1) 13 (0/1)
9 to 15 13 (0/1) 13 (0/1) 13 (0/1)
16 to 25 13 (0/1) 13 (0/1) 13 (0/1)
26 to 50 13 (0/1) 13 (0/1) 13 (0/1)
51 to 90 13 (0/1) 13 (0/1) 13 (0/1)
91 to 150 13 (0/1) 13 (0/1) 50 (1/2)
151 to 280 13 (0/1) 50 (1/2) 50 (1/2)
281 to 500 13 (0/1) 50 (1/2) 80 (2/3)
501 to 1,200 50 (1/2) 80 (2/3) 125 (3/4)
1,201 to 3,200 50 (1/2) 125 (3/4) 200 (5/6)
3,201 to 10,000 80 (2/3) 200 (5/6) 315 (7/8)
10,001 to 35,000 125 (3/4) 315 (7/8) 500 (10/11)
35,001 to 150,000 200 (5/6) 500 (10/11) 800 (14/15)
150,001 to 500,000 315 (7/8) 800 (14/15) 1250 (21/22)
500,001 and over 500 (10/11) 1250 (21/22) 1250 (21/22)

AQL 1.5 at general inspection levels I, II and III

Lot size Level I Level II Level III
2 to 8 8 (0/1) 8 (0/1) 8 (0/1)
9 to 15 8 (0/1) 8 (0/1) 8 (0/1)
16 to 25 8 (0/1) 8 (0/1) 8 (0/1)
26 to 50 8 (0/1) 8 (0/1) 8 (0/1)
51 to 90 8 (0/1) 8 (0/1) 32 (1/2)
91 to 150 8 (0/1) 32 (1/2) 32 (1/2)
151 to 280 8 (0/1) 32 (1/2) 50 (2/3)
281 to 500 32 (1/2) 50 (2/3) 80 (3/4)
501 to 1,200 32 (1/2) 80 (3/4) 125 (5/6)
1,201 to 3,200 50 (2/3) 125 (5/6) 200 (7/8)
3,201 to 10,000 80 (3/4) 200 (7/8) 315 (10/11)
10,001 to 35,000 125 (5/6) 315 (10/11) 500 (14/15)
35,001 to 150,000 200 (7/8) 500 (14/15) 800 (21/22)
150,001 to 500,000 315 (10/11) 800 (21/22) 800 (21/22)
500,001 and over 500 (14/15) 800 (21/22) 800 (21/22)

Legend: the number is the sample size. The first bracketed number is Ac: accept the lot if the number of defective units found is Ac or fewer. The second is Re: reject the lot if the number found is Re or more.

Where the sample size equals or exceeds the lot size, the table calls for 100 percent inspection. This applies to some of the small-lot cells.

At AQL 1.0, every cell from 2 to 8 up to 51 to 90 reads 13 (0/1) at all three levels. At AQL 1.5, every cell from 2 to 8 up to 26 to 50 reads 8 (0/1) at all three levels.

Where the plan comes from another letter

These cells follow an arrow to the plan of another code letter:

  • AQL 1.0, lot 91 to 150, level II: the code letter is F, but the plan used is letter E's, 13 (0/1).
  • AQL 1.5, lot 91 to 150, level II: the code letter is F, but the plan used is letter G's, 32 (1/2).
  • AQL 1.0, lot 500,001 and over, level III: the code letter is R, but the plan used is letter Q's, 1250 (21/22).

Where these tables come from

These tables come from MIL-STD-105E, Sampling Procedures and Tables for Inspection by Attributes (U.S. Department of Defense, 10 May 1989). ANSI/ASQ Z1.4 and ISO 2859-1 descend from it. The tables here were not compared cell by cell with the current paid editions of ANSI/ASQ Z1.4 or ISO 2859-1. Where a contract or purchase order names a standard and an edition, that one governs.

Questions people ask

What sample size does AQL 1.0 give at level II for a lot of 1,201 to 3,200?

The AQL 1.0 table gives 125 (3/4): inspect 125 units, accept the lot if 3 or fewer are defective, and reject it if 4 or more are.

Why can AQL 1.0 and AQL 1.5 give different plans for the same lot?

For lot 91 to 150 at level II, AQL 1.0 gives 13 (0/1) and AQL 1.5 gives 32 (1/2). The code letter is F in both tables, but the arrows in Table II-A send the AQL 1.0 cell to letter E's plan and the AQL 1.5 cell to letter G's plan.

Sources

Checked 11 October 2026.

This page is an unofficial reference, not affiliated with any standards body, and where your contract names ANSI/ASQ Z1.4, ISO 2859-1 or another standard, use the tables of that edition.

AQL Chart Guide