Audience
Developers, product teams, and enterprises seeking to build fast, natural, multilingual voice agents and text-to-speech experiences for customer-facing and business workflows
About Cartesia Sonic-3.6
Sonic is a real-time text-to-speech model built for voice agents, combining natural delivery, sub-90ms latency, and native support for more than 40 languages. It is designed to make voice interactions feel effortless, with tone that adjusts to context, consistent pacing, and speech that follows the natural rhythm of conversation. By default, Sonic interprets the emotional subtext of a transcript and calibrates delivery automatically, while non-verbal expressions such as laughter can be inserted directly into the text. The model follows transcripts faithfully, produces clean audio across languages and voices, and handles alphanumeric content such as order numbers, phone numbers, IDs, and email addresses naturally without preprocessing. Context-aware pronunciation helps heteronyms sound correct from surrounding words, while custom pronunciation dictionaries let teams define how proper nouns and domain-specific terms should be spoken.
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Pricing
Starting Price:
$5 per month
Free Version:
Free Version available.
Free Trial:
Free Trial available.
Integrations
API:
Yes, Cartesia Sonic-3.6 offers API access
No integrations listed.
Company Information
Cartesia
Founded: 2023
United States
www.cartesia.ai/sonic
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Product Details
Platforms Supported
Cloud
Training
Documentation
Support
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