# Handling Errors

All errors are a subclass of `RPCError` which has a `.code` and a `.message` attribute.

## Custom errors

GramJS provides some custom helper classes that subclass RPCError like `FloodWaitError` which has a `.seconds` attribute telling you how long to sleep before calling the same request again. 

These errors aren't generated and can be found in `RPCErrorList`.

## Handling flood wait errors

The most common error is the `FloodWait` error which is caused by calling a method multiple times in a short period and acts as a spam filter from telegram. 

By default, GramJS sleeps when the `floodwait` is lower than 60 seconds but this threshold can be easily changed with the `floodSleepThreshold` setter.

```javascript
client.floodSleepThreshold = 300; // sleeps if the wait is lower than 300 seconds
```

The longest wait possible is 1 day which is `24 * 60 * 60` seconds