# 422 Unprocessable Content

Well-formed data whose values break the rules.

## What is **422 Unprocessable Content**?

**422 Unprocessable Content** means the JSON is well-formed but the values break the rules, like a start date after the end date. Some APIs use 400 for this instead.

Level: Journeyman · [More Web Development terms at this level](https://www.ask-codey.com/glossary/subjects/web-development/journeyman)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/422-unprocessable-content