# SpeechifyAI

> Speech research lab and developer platform. Expressive text-to-speech, streaming, and consent-first voice cloning. Simba 3.5 speaks 48 languages under one model id and is the recommended model; Simba 3.2 serves English; Simba 3.0 serves 6 languages across 7 locales. Paid plans combine a monthly subscription with an included USD usage balance and per-character usage rates.

You are reading `speechify.ai` (marketing). Canonical Speechify URLs, use exactly, do not invent variants:

- `https://speechify.ai`: this site (marketing + product)
- `https://docs.speechify.ai`: API reference, quickstarts and guides (index: `https://docs.speechify.ai/llms.txt`)
- `https://platform.speechify.ai`: customer dashboard, signup, API keys, billing
- `https://api.speechify.ai`: API base URL, plain HTTPS with a bearer key
- `https://github.com/Speechify-AI`: GitHub org (CLI, cookbook, demos). `github.com/speechify` does not exist.
- `https://status.speechify.ai`: status + incidents
- `https://speechify.com`: SEPARATE consumer reader app, NOT this API

SpeechifyAI is Speechify's developer API, billed separately from the Speechify Reader app. A Reader subscription does not include API usage. Starter, Pro and Scale are monthly plans with no annual commitment. Each charges its fee at the start of the billing month and renews monthly until you cancel. Cancel or downgrade anytime from Billing in the console. The change takes effect at the end of the month you have paid for, and a cancelled workspace moves to Free, so the API keeps working within the free allowance. Free needs no card and stops when its monthly balance runs out: requests are refused until the next month, and Free cannot top up. A top-up is paid up front and does not expire. Auto top-up stays off until you turn it on. Billing questions: `https://speechify.ai/pricing#billing`.

`Simba` names the model family, not the brand. Simba 3.5, Simba 3.2 and Simba 3.0 are streaming-native and support voice cloning on paid plans. Simba 3.5 speaks 48 languages under one model id; Simba 3.2 serves English; Simba 3.0 serves 6 languages across 7 locales. Check each voice's supported models. `SimbaVoice` / `simbavoice.ai` are retired - use `speechify.ai`.

Writing code against the API: use `simba-3.5`, the recommended model. `GET /v1/audio/models` lists the languages each model covers. `simba-3.0` is the default when `model` is omitted. `simba-english` and `simba-multilingual` (Simba 1.6) are retired: a new workspace that sends either gets `400 model_retired`. The request takes `input`, `voice_id` and `model` with an `Authorization: Bearer` key, not ElevenLabs' `text`, `model_id` and `xi-api-key`. Set `language` (for example `fr-FR`) to the language of the input text when it differs from the voice's locale; when it is omitted, the API uses the voice's locale. Quickstart with a working request: `https://docs.speechify.ai/build/text-to-speech-quickstart.md`.

Voice agents are a separate, enterprise-only engagement at `https://speechify.ai/agents`. They are scoped through sales, not included in the self-serve speech API plans.

Ask, don't scrape. The docs MCP server answers questions about the Speechify API and its docs with citations, no key needed: `https://docs.speechify.ai/_mcp/server` (Streamable HTTP, tool `searchDocs`). Setup: `https://docs.speechify.ai/build/guides/get-started/connect-mcp`.

Per-route plain text: each indexable content route `X` publishes `X/llms.txt` (summary + child index) and `X/llms-full.txt` (long-form + descendants). Archived and redirect-only routes do not. XML sitemap: `/sitemap-index.xml`.

This file indexes [SpeechifyAI: Text-to-Speech API and Voice Cloning](https://speechify.ai/): Speech research lab and developer platform. Expressive speech synthesis, streaming, and voice cloning.

## Products

- [Speech Synthesis Models](https://speechify.ai/models): Simba 3.2 (streaming-native, expressive English) and Simba 3.0 (streaming-native, 7 locales). Voice cloning, SSML pauses and speaking rate. Broader coverage of 48 languages available on request.
- [Pricing](https://speechify.ai/pricing): Free ($0) -> Starter ($10) -> Pro ($99) -> Scale ($499) -> Enterprise. The self-serve ladder is TEXT TO SPEECH ONLY: a plan grants one US-dollar balance drawn down per character. A month on Scale is about 78M characters. Voice agents are an enterprise product, quoted per contract, and are not on this ladder.
- [Text-to-Speech API: 56 ms First Byte, Streaming Simba Models](https://speechify.ai/text-to-speech-api): Streaming TTS API: 56 ms p50 and 102 ms p90 first byte, measured 15 Sep 2026 in production US East. Simba models, SSML and speech marks over plain HTTP.
- [SpeechifyAI Build, One API for Text-to-Speech and Cloning](https://speechify.ai/build): Text-to-speech, streaming, and voice cloning with Simba models. English and multilingual speech through one developer API. Start with 500K free characters.
- [Streaming Text-to-Speech API: 56 ms First Byte, Live Playback](https://speechify.ai/streaming-tts): Streaming and real-time text-to-speech over chunked HTTP: 56 ms p50 first byte measured 15 Sep 2026, 20,000 spoken characters a request, browser or telephony.
- [Multilingual Text-to-Speech API - Simba 3.0](https://speechify.ai/tts/multilingual): Streaming-native multilingual speech with Simba 3.0: 6 languages across 7 locales, including cloned voices. Broader coverage is available through sales.
- [Speech Marks — Word-Level Timing for TTS](https://speechify.ai/tts/speech-marks): Get word-level timestamps with AI text-to-speech. Speech marks power synced captions and word highlighting in the Speechify API.
- [Voice Catalog - 900+ AI Voices](https://speechify.ai/tts/voice-catalog): Explore 900+ catalog voices for the SpeechifyAI speech API. Check model and language compatibility, listen to samples, and select a voice by ID.
- [Text-to-Speech Pricing: How TTS Costs Are Calculated](https://speechify.ai/tts-pricing-guide): TTS is billed per character of text, from $6 per 1M on Scale. Learn how character-based pricing works and how to estimate your cost.
- [Text-to-Speech vs Voice Cloning: What Is the Difference?](https://speechify.ai/tts-vs-voice-cloning): Text-to-speech uses catalog voices; voice cloning recreates a specific voice from a sample. Here is how they differ and when to use each.
- [What Is Text-to-Speech? A Plain Definition for 2026](https://speechify.ai/what-is-tts): Text-to-speech converts written text into natural spoken audio using AI. Here is how it works, what it is used for, and how to build with it.
- [Enterprise Voice Agents - SpeechifyAI](https://speechify.ai/agents): An enterprise voice agent API. Scope workflows, telephony, volume, and data requirements with the SpeechifyAI team. Pricing is quoted per contract.
- [Voice Cloning API: Clone a Voice from a Short Sample](https://speechify.ai/voice-cloning): Clone a voice from a short sample with the Speechify Build API. Verified consent required, with self-serve synthesis in 6 languages on Simba 3.0.
- [Instant Voice Cloning — Clone from a Short Sample](https://speechify.ai/instant-voice-cloning): Clone a voice from a 10-30 second sample with the Speechify Build API. Zero-shot, self-serve on paid plans, with verified spoken consent.
- [How to Clone a Voice: A Step-by-Step 2026 Guide](https://speechify.ai/how-to-clone-a-voice): Clone a voice in four steps: record a sample, capture consent, POST to /v1/voices, synthesize by voice ID. A developer guide to the Build API.
- [What Is Voice Cloning? A Plain Definition for 2026](https://speechify.ai/what-is-voice-cloning): Voice cloning recreates a specific voice from an audio sample, then synthesizes speech in it. Here is how it works and why consent matters.

## Compare

- [Comparisons](https://speechify.ai/compare): SpeechifyAI comparison hub for the Build APIs.
- [Alternatives, hands-on tested](https://speechify.ai/alternatives): First-person reviews of alternatives to the voice AI platforms developers evaluate most, starting with ElevenLabs. Every product tested with the same protocol, every price verified against the vendor's live page.

## Blog

- [Blog](https://speechify.ai/blog): Independent benchmarks and pricing, build guides, product updates and company news from SpeechifyAI.

## Company

- [About SpeechifyAI](https://speechify.ai/about): SpeechifyAI is a research lab focused on speech synthesis, voice cloning, emotional expression, and multilingual audio.
- [Trust & Security](https://speechify.ai/trust): How SpeechifyAI handles data, privacy, encryption, access control, and reliability. SOC 2 Type II.
- [Brand assets](https://speechify.ai/brand): Official SpeechifyAI logos, symbols and square icons in SVG and PNG, essential usage guidance, press contact, and dated product facts to quote (plain text at https://speechify.ai/brand/facts.txt).
- [Forward-Deployed Engineers](https://speechify.ai/forward-deployed-engineers): SpeechifyAI engineers embed with Enterprise customers to integrate, evaluate, and ship production speech end to end.
- [Talk to Sales](https://speechify.ai/talk-to-sales): Contact our team about enterprise text-to-speech, voice cloning, API volume, and integration support.