Rate limits and error handling
Refer to our list of error codes, rate limits, and ingestion limits for troubleshooting help.
Rate limits
All endpoints are rate limited. Check the response codes for a 429 error, which indicates you have hit a rate limit, and retry requests that exceed the rate limit at a later time. If you consistently hit rate limits, we recommend adjusting your request-rate using an exponential backoff algorithm.
Ingestion limits
Klaviyo's event tracking endpoints use ingestion limits to prevent processing delays and service interruptions to the event ingestion pipeline. If you are using a Klaviyo webhook, custom integration, or API implementation, it is important to be aware of the limits on the events you send into Klaviyo. The table below provides guidance on the maximum sizes for your payload and its fields.
Endpoints with ingestion limits:
/api/events/client/events- legacy
/api/track
| Category | Limit |
|---|---|
| Max payload size | 5 MB decompressed |
| Max number of event properties per data packet | 300 |
| Max size of any field | 100 kB |
| Max number of items in arrays | 4000 |
| Max levels of nested objects | 10 |
| Timestamp of events | Between 2000 and “now”+1 year |
Errors
Our API uses conventional HTTP response codes to indicate success or failure of an API request. Errors typically fall into three ranges:
- 2xx - Success
- 4xx - Error as a result of information provided as part of the request, such as a requested object that doesn't exist, an invalid setting, etc.
- 5xx - Error due to Klaviyo
The response of all API errors contain a message parameter which has developer-facing information about why the request failed.
See the table below for a list of error codes and their corresponding descriptions:
| Code | Summary | Description |
|---|---|---|
| 200 | OK | The request completed successfully |
| 400 | Bad Request | Request is missing or has a bad parameter |
| 400 | Not Authorized | Request is missing or has an invalid API key |
| 401 | Not Authorized | Key is valid, but account does not have permissions to perform this action |
| 403 | Forbidden | Request is missing or has an invalid API key |
| 404 | Not Found | The requested resource doesn't exist |
| 429 | Rate Limit | You hit the rate limit for this endpoint (different endpoints have different rate limits) |
| 500 | Server Error | Something is wrong on Klaviyo's end |
Updated over 2 years ago