Cartesia Sonic
Real-time text-to-speech and voice agents API.
What it is
Sonic bills 1 credit per character, roughly 750 to 800 credits per minute of audio.
Pricing
Free20K credits (~27 min)
$0Pro100K credits (~133 min)
$5/moStartup1.25M credits
$49/moScale8M credits
$299/moBilling basis not confirmed: the official page shows these amounts but does not clearly say whether a price is billed monthly or yearly. Help me choose does not count it as within a budget.
Source: official pricing page. Prices checked Nov 5, 2026. Prices change often.
Sources and caveats
We read these pages for prices and plan details. Feature descriptions summarise what the vendor says and were not tested by us; pros, cons and scores are our opinion. These are third-party sites with their own terms; linking to them does not imply any affiliation.
Pros
- Paid plans from $5 a month
- Built for low-latency voice agents
Cons
- Developer and API oriented
- Pro overage costs $65 per million credits
Where it ranks
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