AQL (Acceptable Quality Limit) is a standard used to determine whether a product batch meets required quality by inspecting a sample rather than the entire batch.

What is a critical defect?

A critical defect rate of 0% is typically required. Critical defects can harm end users, lead to non-compliance, or cause product failure.

What are major and minor defects?

A major defect rate of up to 2.5% and minor defect rate of up to 4% are generally acceptable.

AQL Calculator & Sampling Table

AQL Calculator

Acceptable Quality Limit (AQL) sampling inspects a representative sample of your order instead of every unit. Enter your order quantity, inspection level and the defect AQLs below to get the required sample size and the accept / reject points, based on ISO 2859-1 / ANSI Z1.4 / GB/T 2828.1.

Inspection Parameters

Order Quantity

Inspection Level

Critical Defects

Sample Size—

Accept Point—

Reject Point—

Major Defects

Sample Size—

Accept Point—

Reject Point—

Minor Defects

Sample Size—

Accept Point—

Reject Point—

How to read the result

Sample Size — how many units to inspect from the batch.
Accept Point (Ac) — maximum number of defects allowed to pass the inspection.
Reject Point (Re) — reaching this many defects fails the inspection (always Ac + 1).
Critical defects must always be zero.

Standard notes

Uses ISO 2859-1 / ANSI Z1.4 Table 1 (sample size code letters) and Table 2 (single normal inspection sampling plans).
Where a code letter + AQL has no single-sampling plan, a 100% inspection is required.
Common starting AQLs: 1.5 / 2.5 (major) and 4.0 (minor).
For an inspection plan tailored to your order, contact VICC for a free QC consultation.

What is an AQL Inspection?

AQL (Acceptable Quality Limit) is a standard used to determine whether a product batch meets the required quality by inspecting a sample rather than the entire batch. It is based on international standards (ISO 2859) and is widely used to decide if a product order is acceptable or should be rejected.

AQLs can be set for a percentage or a number of defects. At VICC, our inspectors check a sample of the shipment for issues with performance, usability, functionality and appearance. If everything meets the agreed standards, a certificate is issued to confirm the product quality.

Acceptance rate: 0%

Critical Defects

A 0% critical defect rate is typically required, as critical defects are unacceptable. They can pose harm to the end user, lead to non-compliance with local regulations, or cause product failure. Critical defects are the most severe among the three types of defects — these flaws make a product entirely unusable and expose companies to avoidable risks, including product liability concerns, legal actions, and potential recalls.

Acceptance rate: up to 2.5%

Major Defects

A major defect rate of up to 2.5% is generally acceptable. Major defects have a negative impact on the product's performance, functionality and appearance, and often represent noticeable issues that are easy to detect by the final user.

Acceptance rate: up to 4%

Minor Defects

A minor defect rate of up to 4% is generally acceptable. These defects represent small deviations from product specifications that most buyers would still tolerate. Minor defects do not affect the product's performance or functionality and are often unnoticed by the end user.

What are the benefits of AQL quality control inspections?

AQL can be a more practical alternative to testing every product in a batch. While testing everything is manageable with small volumes, larger orders make this difficult due to time and cost constraints. AQL has been a trusted method for years, though it doesn't guarantee a defect-free result since some issues may go unnoticed.

AQL simply allows you to select the percentage of defects that you are willing to accept, and it can be a sensible option when it comes to gaining valuable insights about the products in your supply chain.