Frequently Asked Questions

Our RESTful API is a Text-to-Speech (TTS) API service that allows developers to convert text into spoken audio using high-quality AI voices. Our API can be used in a wide-range of applications — voice assistants, long-form narration, interactive voice response (IVR) systems and more. We’ve collaborated with professional voice actors to develop the highest quality AI voice models that boast over 150 combinations of voices and styles, ensuring that the data used to create our natural-sounding synthetic voices is secure, high quality and developed ethically.

The API has a basic and streaming TTS (text-to-speech) endpoint. The API will accept some SSML tags, such as and we offer an avatar endpoint to quickly pull a list of all available voices and their metadata.

Our rate limits start at 15 requests / 3 seconds.

The render speed is considered to be the total amount of time it takes to play back audio after the entire text has been rendered. WellSaid API has a fastest render speed of approximately 500ms per 35 characters, ensuring seamless voice integration for your application. The total render speed can vary based on factors like text length, voice selection, and integration method with your technology stack.

Time to first byte (TTFB) measures the time it takes for the server to send the first byte of data in response to the client's request. Our streaming endpoint delivers audio in real-time as it's generated, significantly reducing TTFB. For applications needing low latency, the streaming endpoint is recommended.

Responses are returned an mp3 file.

We offer over 150 high-quality English voices and styles with a diverse range of regional and international accents. We are working towards German, French and Spanish voices with the anticipated release in later 2024. For more information about international languages, contact our support specialists.

Yes! Contact our product support specialists to help deploy a custom voice to your API.