AQL Calculator

Calculate sample sizes and acceptable defect limits according to ISO 2859-1 standard

Lot Information

Lot Size (Total Pieces):

Inspection Level:

AQL Specifications

Critical Defects AQL:

Major Defects AQL:

Minor Defects AQL:

Calculation Results

Based on your input values

Sample Size

–

pieces to inspect

Sample Code

–

ISO 2859-1

Critical Defects

–

max allowed

Major Defects

–

max allowed

Minor Defects

–

max allowed

ISO 2859-1 Sample Size Table (Level II – Normal)

Lot Size Range	Sample Code	Sample Size
2-8	A	2
9-15	B	3
16-25	C	5
26-50	D	8
51-90	E	13
91-150	F	20
151-280	G	32
281-500	H	50
501-1,200	J	80
1,201-3,200	K	125
3,201-10,000	L	200
10,001-35,000	M	315
35,001-150,000	N	500
150,001-500,000	P	800
500,001+	Q	1,250

AQL Acceptance Table (Max Defects Allowed)

Sample Size	AQL 0.25	AQL 0.4	AQL 1.0	AQL 1.5	AQL 2.5	AQL 4.0	AQL 6.5	AQL 10
2	0	0	0	0	0	0	1	1
3	0	0	0	0	0	0	1	1
5	0	0	0	0	0	1	1	1
8	0	0	0	0	1	1	1	2
13	0	0	0	0	1	1	2	2
20	0	0	0	1	1	2	2	3
32	0	0	1	1	2	2	3	5
50	0	0	1	2	2	3	5	7
80	0	1	2	2	3	5	7	10
125	1	1	2	3	5	7	10	14
200	1	2	3	5	7	10	14	21
315	2	2	5	7	10	14	21	21
500	2	3	7	10	14	21	21	21

How to Use This Calculator:

Enter your lot size and select inspection level
Choose your desired AQL values for each defect category
Click “Calculate AQL” to see your results
Use the tables below to manually verify calculations
Example: Lot of 1000 → Sample Size 80 → AQL 2.5 allows max 3 major defects

About AQL (Acceptance Quality Limit)

AQL is a statistical sampling method used in quality control to determine the maximum number of defects acceptable in a shipment while still maintaining overall quality standards.

Sample Size: The number of units randomly selected from your lot for inspection.

Defect Categories:

• Critical: Defects that could cause injury or pose safety risks

• Major: Defects that affect functionality or usability

• Minor: Cosmetic defects that don’t affect functionality

Note: This calculator follows ISO 2859-1 standard for single sampling plans with normal inspection severity.