Models
Learn about latest models, changelog, and deprecations.
Soniox Speech-to-Text AI provides multiple models for real-time and asynchronous transcription and translation. This page lists the currently available models, their capabilities, and important updates.
The following models are deprecated and will be retired on November 30, 2025:
stt-async-preview-v1stt-rt-preview-v2
These models will continue to function until that date but will no longer receive updates or maintenance.
Please migrate to the latest models (stt-async-v3, stt-rt-v3) before November 30, 2025 to ensure uninterrupted service.
Current models
Model | Type | Status |
|---|---|---|
| stt-rt-v3 | Real-time | Active |
| stt-async-v3 | Async | Active |
| stt-rt-preview-v2 | Real-time | Deprecated, will be retired on November 30, 2025 |
| stt-async-preview-v1 | Async | Deprecated , will be retired on November 30, 2025 |
Aliases
Aliases provide a stable reference so you don’t need to change your code when newer versions are released.
| Alias | Points to | Notes |
|---|---|---|
| stt-rt-v3-preview | stt-rt-v3 | Always points to the latest real-time active model |
Changelog
October 21, 2025
New models: stt-rt-v3, stt-async-v3
Replaces: stt-rt-preview-v2, stt-async-preview-v1
Overview
The v3 models introduce major improvements across recognition, translation, and reasoning — making Soniox faster, more accurate, and more capable than ever before.
These models power real-time and asynchronous speech processing in 60+ languages, with enhanced accuracy, robustness, and context understanding.
Key improvements
- Higher transcription accuracy across 60+ languages
- Improved multilingual switching — seamless recognition when speakers change language mid-sentence
- Significantly higher translation quality, especially for languages such as German and Korean
- The async model now also supports translation
- Support for new advanced structured context, enabling richer domain- and task-specific adaptation
- Enhanced alphanumeric accuracy (addresses, IDs, codes, serials)
- More accurate speaker diarization, even in overlapping speech
- Extended maximum audio duration to 5 hours for both async and real-time models
API compatibility
- The v3 models are fully compatible with the existing Soniox API, if you are not using the context feature.
- To upgrade, simply replace the model name in your API request:
{ "model": "stt-rt-v3" }for real-time{ "model": "stt-async-v3" }for async
- If you are using the context feature, update to the new structured context for improved accuracy.
Deprecation notice
The following preview models are deprecated and will be retired on November 30, 2025:
- stt-async-preview-v1
- stt-rt-preview-v2
Please migrate to the v3 models before that date to ensure uninterrupted service. Remove Deprecations section entirely
August 15, 2025
- Deprecated
stt-rt-preview-v1
August 5, 2025
- Released
stt-rt-preview-v2- Higher transcription accuracy
- Improved translation quality
- Expanded to support all translation pairs
- More reliable automatic language switching Replaces: stt-rt-preview-v2, stt-async-preview-v1