# (Deprecated) Rate Limiting & Best Practices

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This API is deprecated. Please use the [E-Waybill APIs from the unified set available here](https://docs.cleartax.in/cleartax-docs/e-invoicing-api/introduction-to-e-invoicing-api).
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**Rate Limiting** : Currently, there is no rate limit. You are requested to apply judicial discretion while using ClearTax APIs to ensure overall level of service on our API server for all users.

**Best Practices :** 

1. Upload only 1 file at a time.
2. Space out multiple requests evenly to reduce load on our server.
3. Limit file size to 1 Mb to ensure faster processing and validation.
4. While there is practically no limitation on the number of rows or documents per file, for the purpose of optimization, we have a maximum limit of 250 line items per document in a file.