Limits & Errors
Rate limits, error codes, and best practices.
Rate Limits
- Default: 50 requests/second per API key
- Configurable: Per-key limits in admin (unlimited or custom throttle)
- Concurrent WebSocket connections: 5 per API key
- Subscriptions per connection: 10
eth_getLogs Block Range
Monad nodes limit the block range per eth_getLogs request (typically 100 blocks). Atlas validates before forwarding. Keep toBlock - fromBlock ≤ 100 blocks; chunk larger ranges. See RPC.
Error Responses
| Status | Meaning |
|---|---|
401 Unauthorized |
Missing or invalid API key |
429 Too Many Requests |
Rate limit exceeded. Response includes retryAfter (seconds). |
400 Bad Request |
Invalid params (e.g. bad address format) |
JSON-RPC -32602 |
block range too large — Chunk eth_getLogs into ≤100 blocks per request |
500 Internal Server Error |
Server error. Check response body for details. |