Error Decoder
Paste a React error and get the cause, the fix, and how to prevent it.
What it does
The Error Decoder takes a React error or warning and explains it in plain English: the likely cause, a concrete fix (with a snippet where it helps), and how to prevent it next time. No more pasting cryptic messages into a search engine and scrolling through unrelated threads.
It's tuned for React-specific issues — hydration mismatches, missing keys, invalid hook calls, dependency warnings, and the rest — so the answers are practical rather than generic.
Example
You paste
Warning: Each child in a list should have a unique "key" prop.
You get
Cause: list items rendered without a stable key. Fix: add key={item.id} to the mapped element. Prevent: never use array index as key for dynamic lists.
Use cases
- Decoding console warnings during development.
- Debugging build or runtime errors without leaving your flow.
- Understanding the root cause so the same error doesn't return.
FAQ
What should I paste?
The full error or warning text. Including the surrounding stack trace or the relevant component helps produce a more targeted fix.
Does it cover hydration and server-rendering errors?
Yes — hydration mismatches, server/client divergence, and invalid hook calls are common cases it handles well.
Will it give me a fix or just the cause?
Both. Every answer is structured as Cause, Fix, and Prevent, with a short code snippet when one helps.