> ## Documentation Index
> Fetch the complete documentation index at: https://assemblyai.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Am I charged for transcribing silent audio?

Yes, our billing is based on audio duration, not the amount of speech content. However, you can use the `speech_threshold` parameter to avoid processing files with minimal speech content. This parameter lets you specify a minimum percentage of speech required for transcription.

[Learn more about speech threshold](/guardrails/set-minimum-speech-threshold)