This is a reference entry from React error codes. A full explanation with fixes has not been written yet.
Context can only be read while React is rendering. In classes, you can read it in the render method or getDerivedStateFromProps. In function components, you can read it directly in the function body, but not inside Hooks like useReducer() or useMemo().
%s is filled in by React at runtime.
- Category
- Minified React error
- Severity
- error
- Runtime
- both
or press Cmd/Ctrl + Enter. The text is only sent to this site to match it.
Source: React error codes. Data fetched 2026-09-25T01:43:12.928Z.