---
title: WCAG 2.0 A/AA Principles and Checkpoints
description: The Web Accessibility Initiative (WAI) of the Worldwide Web Consortium (W3C) has created recognized international guidelines for website accessibility. These guidelines, which are set out in the Web Content Accessibility Guidelines (WCAG), detail how to make websites accessible to all individuals with disabilities.
---

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# WCAG 2.0 A/AA Principles and Checkpoints

# WCAG 2.0 A/AA Has 38 Checkpoints, Categorized by 4 Principles

## Principle 1: Perceivable

Information and user interface components must be presented to users in ways they can perceive. This means that users must be able to comprehend the information being depicted: *It can't be invisible to all their senses*. 

- [Checkpoint 1.1.1: Nontext Content Level (A)](https://www.boia.org/wcag2/cp/1.1.1?hsLang=en)
- [Checkpoint 1.2.1: Prerecorded Audio only and Video-only Level (A)](https://www.boia.org/wcag2/cp/1.2.1?hsLang=en)
- [Checkpoint 1.2.2: Captions (Prerecorded) Level (A)](https://www.boia.org/wcag2/cp/1.2.2?hsLang=en)
- [Checkpoint 1.2.3: Audio Description or Media Alternative (Prerecorded) Level (A)](https://www.boia.org/wcag2/cp/1.2.3?hsLang=en)
- [Checkpoint 1.2.4: Captions (Live) Level (AA)](https://www.boia.org/wcag2/cp/1.2.4?hsLang=en)
- [Checkpoint 1.2.5: Audio Description (Prerecorded) Level (AA)](https://www.boia.org/wcag2/cp/1.2.5?hsLang=en)
- [Checkpoint 1.3.1: Info and Relationships Level (A)](https://www.boia.org/wcag2/cp/1.3.1?hsLang=en)
- [Checkpoint 1.3.2: Meaningful Sequence Level (A)](https://www.boia.org/wcag2/cp/1.3.2?hsLang=en)
- [Checkpoint 1.3.3: Sensory Characteristics Level (A)](https://www.boia.org/wcag2/cp/1.3.3?hsLang=en)
- [Checkpoint 1.4.1: Use of Color Level (A)](https://www.boia.org/wcag2/cp/1.4.1?hsLang=en)
- [Checkpoint 1.4.2: Audio Control Level (A)](https://www.boia.org/wcag2/cp/1.4.2?hsLang=en)
- [Checkpoint 1.4.3: Contrast (Minimum) Level (AA)](https://www.boia.org/wcag2/cp/1.4.3?hsLang=en)
- [Checkpoint 1.4.4: Resize text Level (AA)](https://www.boia.org/wcag2/cp/1.4.4?hsLang=en)
- [Checkpoint 1.4.5: Images of Text Level (AA)](https://www.boia.org/wcag2/cp/1.4.5?hsLang=en)

## Principle 2: Operable

User interface components and navigation must be operable: *The interface cannot require interaction that a user cannot perform*. 

- [Checkpoint 2.1.1 Keyboard Level (A)](https://www.boia.org/wcag2/cp/2.1.1?hsLang=en)
- [Checkpoint 2.1.2: No Keyboard Trap Level (A)](https://www.boia.org/wcag2/cp/2.1.2?hsLang=en)
- [Checkpoint 2.2.1: Timing Adjustable Level (A)](https://www.boia.org/wcag2/cp/2.2.1?hsLang=en)
- [Checkpoint 2.2.2: Pause, Stop, Hide Level (AA)](https://www.boia.org/wcag2/cp/2.2.2?hsLang=en)
- [Checkpoint 2.3.1: Three Flashes or Below Threshold Level (A)](https://www.boia.org/wcag2/cp/2.3.1?hsLang=en)
- [Checkpoint 2.4.1: Bypass Blocks Level (A)](https://www.boia.org/wcag2/cp/2.4.1?hsLang=en)
- [Checkpoint 2.4.2: Page Titled Level (A)](https://www.boia.org/wcag2/cp/2.4.2?hsLang=en)
- [Checkpoint 2.4.3: Focus Order Level (A)](https://www.boia.org/wcag2/cp/2.4.3?hsLang=en)
- [Checkpoint 2.4.4: Link Purpose (In Context) Level (A)](https://www.boia.org/wcag2/cp/2.4.4?hsLang=en)
- [Checkpoint 2.4.5: Multiple Ways Level (AA)](https://www.boia.org/wcag2/cp/2.4.5?hsLang=en)
- [Checkpoint 2.4.6: Headings and Labels Level (AA)](https://www.boia.org/wcag2/cp/2.4.6?hsLang=en)
- [Checkpoint 2.4.7: Focus Visible Level (AA)](https://www.boia.org/wcag2/cp/2.4.7?hsLang=en)

## Principle 3: Understandable

Information and the operation of a user interface must be understandable: *Users must be able to understand the information as well as the operation of the user interface*. 

- [Checkpoint 3.1.1: Language of Page Level (A)](https://www.boia.org/wcag2/cp/3.1.1?hsLang=en)
- [Checkpoint 3.1.2: Language of Parts Level (AA)](https://www.boia.org/wcag2/cp/3.1.2?hsLang=en)
- [Checkpoint 3.2.1: On Focus Level (A)](https://www.boia.org/wcag2/cp/3.2.1?hsLang=en)
- [Checkpoint 3.2.2: On Input Level (A)](https://www.boia.org/wcag2/cp/3.2.2?hsLang=en)
- [Checkpoint 3.2.3: Consistent Navigation Level (AA)](https://www.boia.org/wcag2/cp/3.2.3?hsLang=en)
- [Checkpoint 3.2.4: Consistent Identification Level (AA)](https://www.boia.org/wcag2/cp/3.2.4?hsLang=en)
- [Checkpoint 3.3.1: Error Identification Level (A)](https://www.boia.org/wcag2/cp/3.3.2?hsLang=en)
- [Checkpoint 3.3.2: Labels or Instructions Level (A)](https://www.boia.org/wcag2/cp/3.3.2?hsLang=en)
- [Checkpoint 3.3.3: Error Suggestion Level (AA)](https://www.boia.org/wcag2/cp/3.3.3?hsLang=en)
- [Checkpoint 3.3.4: Error Prevention (Legal, Financial, Data) Level (AA)](https://www.boia.org/wcag2/cp/3.3.4?hsLang=en)

## Principle 4: Robust

Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies: *As technologies and user agents evolve, the content should remain accessible*. 

- [Checkpoint 4.1.1: Parsing Level (A)](https://www.boia.org/wcag2/cp/4.1.1?hsLang=en)
- [Checkpoint 4.1.2: Name, Role, Value Level (A)](https://www.boia.org/wcag2/cp/4.1.2?hsLang=en)

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