As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/m/cartesia-ink-2/

# Cartesia Ink-2 (streaming STT)

Cartesia, Ink family. Status: current. Type: speech and audio. Released: 2026-07-09.

## How to call it

| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| Cartesia API | `ink-2` | wss://api.cartesia.ai/stt/websocket?model=ink-2 | https://docs.cartesia.ai/build-with-cartesia/stt/latest |
| Cartesia API (beta) | `ink-preview` | wss://api.cartesia.ai/stt/websocket |  |

## Pricing

- Price not published.
- Last checked: 2026-09-29

## Specs

- Input: audio
- Output: text
- Context window: not published
- Max output: not published
- Open weights: no
- Licence: proprietary

## Where it stands

- Newer speech and audio models in the registry since its release: 44. The 5 newest:
  - NVIDIA Nemotron 3.5 Transcribe (30B-A4B) (2026-10-28) https://postcutoff.com/m/nemotron-3-5-transcribe/
  - Hy-SimulMT-30B-A3B (2026-10-22) https://postcutoff.com/m/hy-simulmt-30b-a3b/
  - Eleven Realtime v1 Max / Mini (2026-10-20) https://postcutoff.com/m/eleven-realtime-v1-max/
  - Voxtral Mini Transcribe 3 (+ Mini Transcribe Realtime 3) (2026-10-20) https://postcutoff.com/m/voxtral-mini-transcribe-3/
  - Voxtral Small Transcribe 3 (2026-10-20) https://postcutoff.com/m/voxtral-small-transcribe-3/
- After it from Cartesia: Cartesia Sonic-3.6 (2026-08-27) https://postcutoff.com/m/cartesia-sonic-3-6/
- Closed weights; access is hosted only.

## What stands out

- Built-in semantic turn detection: Emits turn.start / turn.update / turn.eager_end / turn.resume / turn.end events so agents need no separate VAD; 89% precision, 93% F1 on endpointing; ~0.1 s time-to-final-transcript. Source: https://www.cartesia.ai/blog/introducing-ink-2
- #1 streaming WER on Artificial Analysis at launch: 3.4% WER on AA-AgentTalk, ranked #1 on Artificial Analysis's streaming STT leaderboard (company claim, July 2026). Source: https://www.cartesia.ai/blog/introducing-ink-2
- Keyterm prompting (found after launch): Keyterm prompting and configurable turn detection added 2026-08-11. Source: https://www.cartesia.ai/blog

## Notes

Launched English-only (blog 2026-07-09); the current stable `ink-2` snapshot is dated 2026-09-17 and supports English, French, Hindi, Japanese, Spanish. Some press dates an earlier Ink 2 release to May 2026 (unverified). Query params: model, encoding, sample_rate, cartesia_version=2026-08-14; send `finalize` when user stops. Older model: ink-whisper (1 credit/s streaming). Ink-2 credit price not found on pricing page (plans list included STT hours).

Cartesia's streaming speech-to-text built for voice agents; pairs with Sonic-3.6.

Sources: https://docs.cartesia.ai/build-with-cartesia/stt/latest , https://docs.cartesia.ai/api-reference/stt/stt , https://www.cartesia.ai/blog/introducing-ink-2

Model page: https://postcutoff.com/m/cartesia-ink-2/