Realistic text to speech
What "realistic" is made of
A synthetic voice gives itself away in specific places: delivery that ignores the sentence, numbers read like a modem, and a pause long enough for the caller to say "hello?" twice. Sonic is built around those failure modes.
Ranked first in blind listening tests
Sonic has held #1 on Artificial Analysis's controlled-voice and provider-voice leaderboards since the Sonic-3.6 release in September 2026, and blind listeners rank it first on VoiceArena. Both boards update as new models ship; we link them in the FAQ so you can check the current standings.
Streams while it speaks
Sonic starts playing audio before it finishes generating the sentence, with sub-90ms model latency. A voice can sound flawless in a downloaded file and still fail a live conversation; the same model has to carry both.
Says the messy parts like a person
Times, prices, confirmation codes, and acronyms are where synthetic voices usually break. Sonic reads numbers, IDs, and acronyms the way a person would say them, so a realistic voice does not lose the illusion on the useful parts of a sentence.
Hear two of the voices
Skylar, storytelling
Daniel, a delivery update
Delivery that follows the sentence
Which word gets the stress, where the pause lands, whether the end of the sentence rises: Sonic reads context, not just words. The same line reads differently as a confirmation, a warning, and a question.
The same voice on take one and take fifty
Realism is also consistency. Pick a voice once and it stays that voice across takes, scripts, and regenerations, in the Playground and through the API, so line fifty sounds like line one.
Fast enough to stay believable
People hand the conversational floor back in about 200 milliseconds. A voice that arrives a second and a half late is not realistic no matter how good it sounds; Sonic's model latency is under 90 milliseconds, so speech stays the smallest part of that budget.
Lifelike, expressive voices for every use case
Support
Power support experiences that delight your customers.
Gaming
Bring your storytelling to life with immersive voices.
Content
Create content that engages viewers and drives clicks.
Media
Narrate content for podcasts, news, and publishing.
Healthcare
Empower healthcare with voices that patients trust.
Sales
Scale sales with lifelike voices that lead to conversions.
Voice Agents
Build responsive AI voice agents for any use case.
Dubbing
Go global with localized voices and accents for every language.
Avatars
Create expressive, relatable AI avatars for any use case.
Logistics
Automate complex logistics with voice-enabled systems.
Recruiting
Screen candidates with AI-powered voice interviews.
Accessibility
Make your content accessible to anyone, anywhere.
Hear it on your own script
01
Open the Playground and pick a voice. Every voice in the library is generated by Sonic, so what you preview is what ships.
02
Paste a passage from your real project, with its numbers, names, and acronyms. Polished demo text hides exactly the parts you need to hear.
03
Press play and listen for the tells: wrong stress, flat pauses, stumbled identifiers. Adjust pace and emotion, then regenerate the lines that need it.
04
Ship the same voice through the API. The voice IDs and settings you auditioned are the ones your application calls.
FAQs
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