# json.JSONEncodeError

- **ID:** `python/json-jsonencodeerror`
- **Domain:** python
- **Category:** encoding_error
- **Verification:** official
- **Fix Rate:** 80%

## Root Cause

JSON encoding failed. Object contains non-serializable data (e.g. bytes, datetime).

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.x | active | — | — |