Supertone API Review
Expressive character voices (games, content, Korean/Japanese/English markets first, now 31 languages via Supertonic 3) on cheap credit-based subscriptions from $2.99/month; uniquely pairs the hosted API with the open OpenRAIL-M Supertonic model for on-device synthesis.
Among the 46 text-to-speech tools we track, Supertone API has the 15th-widest language coverage - a fit for multilingual and localization projects.
From $2.99/mo
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What we know about Supertone API
This is our verified profile of Supertone API, a text-to-speech apis platform - expressive character voices (games, content, Korean/Japanese/English markets first, now 31 languages via Supertonic 3) on cheap credit-based subscriptions from $2.99/month; uniquely pairs the hosted API with the open OpenRAIL-M Supertonic model for on-device synthesis. Every fact about Supertone API below carries the source it came from and the day we checked it.
On pricing, Supertone API starts at $2.99 per month for its entry tier. That is the sticker rate: real production cost usually runs higher once you add a language model, a voice provider, and telephony minutes.
On capabilities, Supertone API covers streaming audio output, instant voice cloning, emotion / style controls, and self-host / on-prem option, and does not offer realtime websocket api. Each of those is verified against Supertone API's own docs or dashboard, not marketing copy.
Supertone API ranks the 15th-widest language coverage of the 46 text-to-speech tools we track, but only 6th of 46 for stock voices, so where it lands for you depends on which of those matters more.
In total we track 15 verified facts for Supertone API today, each linking the primary source it came from so you can check our work - and vendor claims we have not measured ourselves are labeled as such on the Supertone API fact sheet below.
Reviewed by vsref Editorialfacts verified Jul 20, 2026Methodology →
Supertone API pricing
Cheapest paid plan $2.99/mo, verified Jul 20, 2026 (source).
| Monthly volume | $ / 1M chars | $ / audio-min | Monthly bill |
|---|---|---|---|
| 200K chars/moHobby project | $14.95 | $0.0142 | $2.99 |
| 2M chars/moProduct feature | $1.50 | $0.0014 | $2.99 |
| 20M chars/moAt scale | $0.15 | $0.0001 | $2.99 |
Effective rates from published pricing; subscription plans resolve to plan fee plus overage. ~950 characters ≈ 1 audio minute. How we compute costs →
Fact sheet
Every row independently verifiedConsidering a switch? Best Supertone API alternatives →
STT in this stack
Text-to-speech is half of a voice pipeline: the other half is the speech-to-text that listens. Compare transcription engines on accuracy, streaming latency, and per-minute price: Deepgram, AssemblyAI, GPT-4o Transcribe, or the full speech-to-text comparison →
Voice agents in this stack
The engine is one layer: a voice agent speaks through its text-to-speech engine, but orchestration, telephony, and turn-taking come from the agent platform. Compare the platforms builders pair Supertone API with: Pipecat, OpenAI Realtime API, Twilio ConversationRelay, or the full voice-agent comparison →
Distribute it
Most Supertone API voiceover ends up in short-form video, and publishing that video across TikTok, YouTube, and Instagram is a scheduling problem with real per-channel pricing. Compare the schedulers creators actually run: Buffer, Postiz, Mixpost, or the social media scheduling platforms compared →
Avatar video in this stack
A cloned or bring-your-own Supertone API voice does not have to stay audio-only: AI avatar video platforms lip-sync it onto a talking avatar for finished video. Compare the platforms: HeyGen, Synthesia, Hedra, or the full avatar-video comparison →