> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cartesia.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Sonic 3.5

<Note>
  Try out our newest model, Sonic 3.6, now Generally Available! Learn more [here](/build-with-cartesia/tts-models/latest).
</Note>

Sonic 3.5 text-to-speech model has sub-90ms latency and native support for 42 languages. It follows your transcript faithfully, voices confirmation codes and heteronyms correctly without preprocessing, and stays expressive enough to carry a real conversation.

Key Features:

* **42 languages out of the box** — English, Hindi, Spanish, French, German, Japanese, Hebrew, and 35 more, each at native quality
* **Expressive, conversational delivery** — strong pacing and real emotional range, tuned for support and agent transcripts
* **Clean audio across every language and voice**, with no artifacts to edit out
* **Alphanumerics that sound right** — order numbers, phone numbers, IDs, and emails spoken naturally in every language, no preprocessing
* **Context-aware English pronunciation** — heteronyms like *read*, *bass*, and *bow* land correctly from the surrounding words

## Voice selection

Choosing voices that work best for your use case is key to getting the best performance out of Sonic 3.5.

**For voice agents**: We've found stable, pleasant, yet also realistic voices work better for voice agents. Some voices you should try include:

* Katie - en-US Female (ID: `f786b574-daa5-4673-aa0c-cbe3e8534c02`)
* Skylar - en-US Female (ID: `db6b0ed5-d5d3-463d-ae85-518a07d3c2b4`)
* Jameson - en-US Male (ID: `a5136bf9-224c-4d76-b823-52bd5efcffcc`)
* Gemma - en-GB Female (ID: `62ae83ad-4f6a-430b-af41-a9bede9286ca`)
* Archie - en-GB Male (ID: `ef191366-f52f-447a-a398-ed8c0f2943a1`)

For more information and recommendations, see [Choosing a Voice](/build-with-cartesia/capability-guides/choosing-a-voice), or take a look at the featured voices on our [Voice Library](https://play.cartesia.ai/voices).

## Language support

Sonic 3.5 supports the following languages:

<table>
  <tbody>
    <tr>
      <td>English (`en`)</td>
      <td>French (`fr`)</td>
      <td>German (`de`)</td>
      <td>Spanish (`es`)</td>
    </tr>

    <tr>
      <td>Portuguese (`pt`)</td>
      <td>Chinese (`zh`)</td>
      <td>Japanese (`ja`)</td>
      <td>Hindi (`hi`)</td>
    </tr>

    <tr>
      <td>Italian (`it`)</td>
      <td>Korean (`ko`)</td>
      <td>Dutch (`nl`)</td>
      <td>Polish (`pl`)</td>
    </tr>

    <tr>
      <td>Russian (`ru`)</td>
      <td>Swedish (`sv`)</td>
      <td>Turkish (`tr`)</td>
      <td>Tagalog (`tl`)</td>
    </tr>

    <tr>
      <td>Bulgarian (`bg`)</td>
      <td>Romanian (`ro`)</td>
      <td>Arabic (`ar`)</td>
      <td>Czech (`cs`)</td>
    </tr>

    <tr>
      <td>Greek (`el`)</td>
      <td>Finnish (`fi`)</td>
      <td>Croatian (`hr`)</td>
      <td>Malay (`ms`)</td>
    </tr>

    <tr>
      <td>Slovak (`sk`)</td>
      <td>Danish (`da`)</td>
      <td>Tamil (`ta`)</td>
      <td>Ukrainian (`uk`)</td>
    </tr>

    <tr>
      <td>Hungarian (`hu`)</td>
      <td>Norwegian (`no`)</td>
      <td>Vietnamese (`vi`)</td>
      <td>Bengali (`bn`)</td>
    </tr>

    <tr>
      <td>Thai (`th`)</td>
      <td>Hebrew (`he`)</td>
      <td>Georgian (`ka`)</td>
      <td>Indonesian (`id`)</td>
    </tr>

    <tr>
      <td>Telugu (`te`)</td>
      <td>Gujarati (`gu`)</td>
      <td>Kannada (`kn`)</td>
      <td>Malayalam (`ml`)</td>
    </tr>

    <tr>
      <td>Marathi (`mr`)</td>
      <td>Punjabi (`pa`)</td>

      <td />

      <td />
    </tr>
  </tbody>
</table>

## Model snapshots

| Snapshot               | Release Date | Languages                                                                                                                                                              | Status                              |
| ---------------------- | ------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------- |
| `sonic-3.5-2026-05-04` | May 4, 2026  | en, de, es, fr, ja, pt, zh, hi, ko, it, nl, pl, ru, sv, tr, tl, bg, ro, ar, cs, el, fi, hr, ms, sk, da, ta, uk, hu, no, vi, bn, th, he, ka, id, te, gu, kn, ml, mr, pa | <Badge color="green">Stable</Badge> |

## Switching from Sonic 3?

If you're already using Sonic 3, see [Migrating from Sonic 3 to Sonic 3.5](/build-with-cartesia/tts-models/sonic-3-to-sonic-3-5) for what's new and what to know before you switch.

## Older Models

For information on `sonic-3`, `sonic-2`, `sonic-turbo`, and `sonic`, see our page on [Older TTS Models](/build-with-cartesia/tts-models/older-models).

## Where to go next

<CardGroup cols={2}>
  <Card title="Try it out online" icon="arrow-pointer" href="https://www.cartesia.ai/sonic">
    No sign-up or code required
  </Card>

  <Card title="Start building" icon="readme" href="/build-with-cartesia/capability-guides/tts">
    Guides and best practices
  </Card>
</CardGroup>