Speechify.ai

What is Speechify.ai?

Speechify.ai is a developer API that converts text to speech and clones voices using the Simba model family. It supports streaming audio output across 48 languages via a single API endpoint. Voice cloning requires a paid plan, and this product is billed separately from the Speechify reading app.

What are the features of Speechify.ai?

• Text-to-speech streaming

  Sends text to a single streaming API endpoint and receives audio output, with control over voice selection and timing.
• Multilingual synthesis

  The Simba 3.5 model generates speech in 48 languages by setting the language parameter on the request.
• Voice cloning

  Creates a reusable voice from a consented reference recording for subsequent synthesis on paid plans.
• SSML support

  Allows control over pauses and pacing using SSML tags while preserving voice characteristics.
• Per-user rate limiting

  Restricts or blocks individual end users within a workspace using a safety_identifier parameter.

What are the use cases of Speechify.ai?

• Real-time voice agents

  Streaming responses with low latency for interactive applications requiring immediate audio feedback.
• Multilingual content delivery

  Generating native-sounding speech across 48 languages from a single model identifier without switching endpoints.

How to use Speechify.ai?

1. Send API request

   Call the streaming endpoint at https://api.speechify.ai/v1/audio/stream using an authorization bearer token.
2. Define parameters

   Pass a JSON body specifying the input text, model such as simba-3.5, language, and voice_id.
3. Receive audio

   Output the response directly to a file format like speech.mp3.

Speechify.ai Pricing Information:

• Free

  $0 per month; includes 500,000 characters monthly (Simba 3.5: 500,000 until November 21, 2026, then 250,000); usage pauses when the balance runs out; catalog voices, streaming, SSML, commercial use, and community support included.
• Starter

  $10 per month; includes 1.9 million characters monthly (Simba 3.5: 1.9 million until November 21, 2026, then 950,000); Simba 3.5 costs $10 per 1 million characters until November 21, 2026 (list price $20); Simba 3.0 and 3.2 cost $10 per 1 million characters; adds voice cloning; additional usage draws from a top-up balance.
• Pro

  $99 per month; includes 13.5 million characters monthly (Simba 3.5: 13.5 million until November 21, 2026, then 6.75 million); Simba 3.5 costs $8 per 1 million characters until November 21, 2026 (list price $16); voice cloning with no per-plan limit.
• Scale

  $499 per month; includes 78 million characters monthly (Simba 3.5: 78 million until November 21, 2026, then 39 million); Simba 3.5 costs $6 per 1 million characters until November 21, 2026 (list price $12); up to 25 seats and 100 service accounts.
• Enterprise / Custom

  Contact sales for global volume, compliance, and procurement requirements.