# Supertone API Review

> Supertone API review: Expressive character voices (games, content, Korean/Japanese/English markets first, now 31 languages via Supertonic 3) on cheap.

![Supertone API logo](https://www.versusref.com/logos/supertone.png)

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 · facts verified Jul 20, 2026

## 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.

## Supertone API pricing

Cheapest paid plan $2.99/mo, verified Jul 20, 2026 ([source](https://www.supertone.ai/en/api)).

| Monthly volume | $ / 1M chars | $ / audio-min | Monthly bill |
| --- | --- | --- | --- |
| 200K chars/mo | $14.95 | $0.0142 | $2.99 |
| 2M chars/mo | $1.50 | $0.0014 | $2.99 |
| 20M chars/mo | $0.15 | $0.0001 | $2.99 |

Effective rates from published pricing; subscription plans resolve to plan fee plus overage. ~950 characters ≈ 1 audio minute.

## Fact sheet

### Pricing

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Pricing model | Monthly subscription credits shared with Supertone Play | Jul 20 | [source](https://docs.supertoneapi.com/en/docs/production/cost-and-usage.md) |
| Cheapest paid plan | $2.99 | Jul 20 | [source](https://www.supertone.ai/en/api) |
| Free tier quota | 3000 credits per month (~5 min of audio) | Jul 20 | [source](https://www.supertone.ai/en/api) |

### Capabilities

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Streaming audio output | ✓  Yes | Jul 20 | [source](https://docs.supertoneapi.com/en/docs/core-concepts/models.md) |
| Realtime websocket API | ✗  No | Jul 20 | [source](https://docs.supertoneapi.com/en/docs/text-to-speech/stream-speech.md) |
| Voice library size | 200 voices | Jul 20 | [source](https://docs.supertoneapi.com/en/) |
| Instant voice cloning | ✓  Yes | Jul 20 | [source](https://docs.supertoneapi.com/en/user-guide/faq) |
| Languages supported | 31 languages | Jul 20 | [source](https://docs.supertoneapi.com/en/docs/core-concepts/models.md) |
| Emotion / style controls | ✓  Yes | Jul 20 | [source](https://docs.supertoneapi.com/en/) |

### Compliance & trust

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Self-host / on-prem option | ✓  Yes | Jul 20 | [source](https://github.com/supertone-inc/supertonic) |
| Model weights license | OpenRAIL-M (Supertonic model weights) | Jul 20 | [source](https://github.com/supertone-inc/supertonic) |

### Build experience

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Official SDKs | Official Python and TypeScript SDKs for the hosted API | Jul 20 | [source](https://docs.supertoneapi.com/en/) |
| Concurrency on base plan | 20 requests per minute (Free and Starter) | Jul 20 | [source](https://www.supertone.ai/en/api) |
| Output formats | WAV | Jul 20 | [source](https://docs.supertoneapi.com/en/) |
| Max input per request | 300 characters per request (raw API) | Jul 20 | [source](https://docs.supertoneapi.com/en/user-guide/faq) |

Source: https://www.versusref.com/tts/tools/supertone/