Amazon Transcribe
Developer Guide

Guidelines and Limits

Supported Regions

For a list of AWS Regions where Amazon Transcribe is available, see AWS Regions and Endpoints in the Amazon Web Services General Reference.


For information about throttling for Amazon Transcribe and to request a limit increase, see Amazon Transcribe Limits in the Amazon Web Services General Reference.


For best results:

  • Use a lossless format, such as FLAC or WAV, with PCM 16-bit encoding.

  • Use a sample rate of 8000 Hz for low-fidelity audio and 16000 Hz for high-fidelity audio.

Amazon Transcribe may store your content to continuously improve the quality of its analysis models. See the Amazon Transcribe FAQ to learn more. To request that we delete content that may have been stored by Amazon Transcribe, open a case with AWS Support.


Amazon Transcribe has the following limitations:

Description Limit
Maximum audio file length 4 hours
Maximum audio file size 2 GB
Maximum size of a custom vocabulary 50 KB
Maximum length of a custom vocabulary phrase 256 characters
Number of days that job records are retained 90