- Home
- Text-to-speech tools
- Cartesia Sonic
Cartesia Sonic
Cartesia Sonic · San Francisco, California, United States · founded 2023
What it is
Cartesia Sonic is a text-to-speech model for real-time voice applications, with sub-90ms latency and support for 44 languages. It can interpret emotional subtext and add non-verbal expressions such as laughter to transcripts. Its localization feature carries emotion, tone, and speaker identity into other languages, while custom pronunciation dictionaries let users specify how proper nouns and domain terms should be spoken.
Sonic is offered through the web and API, and commercial use is included in the Pro plan. Free costs nothing and includes 20K monthly credits and two concurrent text-to-speech requests. Pro costs $5/mo and includes 100K monthly credits, three concurrent requests, commercial use, and instant voice cloning. Startup costs $49/mo and includes 1.25M monthly credits, Pro voice cloning, and organizations. Scale costs $299/mo and includes 8M monthly credits, priority support, and high concurrency limits. Enterprise lists custom credits and agent usage, with no price provided. Managed Agents combine Ink-2 speech-to-text, a chosen LLM, and Sonic-3.6 text-to-speech, with turn-taking and interruption handling. Cartesia lists on-premise, customer VPC, and OEM deployment options.
For and against
For
- Sub-90ms latency and 44-language support.
- Localization carries emotion, tone, and speaker identity.
- Custom pronunciation dictionaries support domain terms.
- API access and commercial use are available.
- Free plan includes 20K monthly credits.
Against
- Free plan allows two concurrent requests.
- Higher monthly credit allowances require paid plans.
The verdict
Cartesia Sonic pairs low-latency text-to-speech with multilingual support and voice-agent capabilities. The free tier has a defined monthly credit allowance, while paid plans add higher allowances and features such as voice cloning and priority support.
Who it suits
Cartesia Sonic may suit developers or teams building real-time voice applications, including voice agents. Its language, localization, pronunciation, and deployment options may also be relevant to projects with specific speech requirements.
Plans and prices
Pro
100K credits / month · $5 prepaid agents / month · Commercial use license · Instant voice cloning
Read 1 Oct 2026 · cartesia.ai
Startup
1.25M credits / month · $49 prepaid agents / month · Pro voice cloning · Organizations
Read 1 Oct 2026 · cartesia.ai
Scale
8M credits / month · $299 prepaid agents / month · Priority support · High concurrency limits
Read 1 Oct 2026 · cartesia.ai
Free
20K credits / month · $1 prepaid agents / month · Text to Speech · Speech to Text
Read 1 Oct 2026 · cartesia.ai
Enterprise
Custom credits & agent usage · Volume pricing · Custom concurrency limits · DPAs and BAAs
Read 1 Oct 2026 · cartesia.ai
On the record
- API access
- Yescartesia.ai · read 20 Sep 2026
- Commercial use
- Yescartesia.ai · read 20 Sep 2026
- Concurrency
- The Free plan lists two concurrent Sonic text-to-speech requests, while Pro lists three.cartesia.ai · read 1 Oct 2026
- Deployment
- Cartesia says Sonic can be deployed on-premise, in a customer VPC on AWS, GCP, or Azure, or through OEM licensing.cartesia.ai · read 1 Oct 2026
- Emotion
- Sonic interprets emotional subtext and can insert non-verbal expressions such as laughter into transcripts.cartesia.ai · read 1 Oct 2026
- Integrations
- Managed Agents can use Cartesia-provisioned numbers, import Twilio numbers, or connect a carrier over SIP.cartesia.ai · read 1 Oct 2026
- Languages
- Sonic supports 44 languages.cartesia.ai · read 1 Oct 2026
- Latency
- Sonic has sub-90ms latency.cartesia.ai · read 1 Oct 2026
- Localization
- Sonic can localize an audio clip into other languages while carrying over emotion, tone, and speaker identity.cartesia.ai · read 1 Oct 2026
- Product
- Sonic is a text-to-speech model for real-time voice applications.cartesia.ai · read 1 Oct 2026
- Pronunciation
- Custom pronunciation dictionaries let users specify pronunciations for proper nouns and domain terms.cartesia.ai · read 1 Oct 2026
- Security
- Cartesia lists HIPAA compliance, SOC 2 Type 2, GDPR, and PCI on the Sonic page.cartesia.ai · read 1 Oct 2026
- Paid from
- 5cartesia.ai · read 20 Sep 2026
- Support
- Cartesia's documentation directs users to Discord to chat with the Cartesia team and community for help.docs.cartesia.ai · read 1 Oct 2026
- Voice agents
- Managed Agents combine Ink-2 speech-to-text, a chosen LLM, and Sonic-3.6 text-to-speech with turn-taking and interruption handling.cartesia.ai · read 1 Oct 2026
- Voice cloning
- Instant voice cloning can use 10 seconds of audio, while Pro Voice Clone training uses 30 minutes or more from one speaker.cartesia.ai · read 1 Oct 2026
