Choosing the Best Text-to-Speech: A Comprehensive Guide

Choosing the best Text-to-Speech (TTS) depends on your needs and requirements.

Quality

TTS should produce a natural-sounding voice that is comfortable to listen to for extended periods. It should be clear and easily understandable, even at different speeds or volumes. Above minimum requirements, the quality can be subjective and requirements vary. Some use cases, requiring voice cloning, especially in media and entertainment, require higher quality.

Compatibility

Ensure TTS is compatible with your hardware, software, and programming language choices. It should also support your audio format choice such as MP3 or WAV, if needed.

Ease of Use

Check the user-friendliness of TTS alternatives to understand how much developer resources you should allocate to integrate them into your application. Easy-to-use TTS with clear documentation and regular maintenance significantly cuts development costs and time.

Cost

TTS alternatives offer different pricing, some charge per character, while others offer subscription plans. Open-source ones may offer the basic features for free and charge for extra features and support, while others require internal expertise to get it up and running.

Language Support

Language and accent support is important for multilingual applications. American English can be sufficient for some applications, while others require a wide variety.

Latency

Latency and speed requirements vary among applications. Low latency TTS ensures minimal delay between the text input and the spoken output. Speed is crucial for interactive applications to maintain responsiveness. However, it may not be important while recording podcasts or movies.

Scalability

If you expect high volumes of text or multiple simultaneous requests, ensure the TTS system can scale to meet these demands or use on-device (decentralized) TTS.

Real-time Processing

If you have a real-time interactive application, make sure TTS is capable of continuous text processing. Continuity is crucial for maintaining a natural conversation flow. This capability is required for LLM applications where the response is generated on the fly.

Reliability

Reliability is not a concern for on-device TTS as it’s always available. It also may not be a big concern for non-streaming applications. Yet, uptime, and high availability, are key for cloud-dependent TTS APIs.

Customization Options

If customizing the voice, speed, pitch, and other aspects of the speech output is important, ensure the TTS you choose offers them and has enterprise support.

Support and Community

If you’re building a commercial application, ensure the level of support that you require and get. If you’re building a hobby project having community support can be sufficient.

We gathered the top free and enterprise-grade Text-to-Speech APIs and SDKs. If you need help choosing the best TTS for your application, you can get expert help from Picovoice Consulting to get a reproducible benchmark developed for you.