body: Google sells access to their TTS service at <https://cloud.google.com/text-to-speech/>. They advertise that you can use it for free, if you use less than 4 million letters (1 million for WaveNet voices).
  
  
  I couldn't find any information regarding the license terms of the generated audio files. So, what may I do with the generated sound files? I mean often you need the same sounds again and again. May I cache the sound files? May I play them to the public? Redistribute them with my app? Offer them as a download? Sell them?
  
  
  To use the TTS service you have to accept the Google Cloud Platform Terms of Service (<https://console.cloud.google.com/tos?id=cloud>). I think the most relevant part is the following section:
  
  
  
  > 
  > 5.1 Intellectual Property Rights. Except as expressly set forth in this Agreement, this Agreement does not grant either party any rights,
  >  implied or otherwise, to the other’s content or any of the other’s
  >  intellectual property. As between the parties, Customer owns all
  >  Intellectual Property Rights in Customer Data and the Application or
  >  Project (if applicable), and Google owns all Intellectual Property
  >  Rights in the Services and Software.
  > 
  > 
  > 
  
  
  
title: Can I use the sound files, generated by the Google Cloud Text-to-Speech freely?