# error: http: request header too large

- **ID:** `go/net-http-request-header-too-large`
- **Domain:** go
- **Category:** config_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The HTTP request headers exceed the server's maximum header size limit, typically 1MB by default.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.20 | active | — | — |
| 1.21 | active | — | — |

## Workarounds

1. **Set a reasonable MaxHeaderBytes on the server** (95% success)
   ```
   server := &http.Server{
    Addr: ":8080",
    MaxHeaderBytes: 1 << 20, // 1 MB
}
   ```

## Dead Ends

- **Increasing server MaxHeaderBytes arbitrarily** — May allow denial-of-service attacks; better to reduce header size. (40% fail)