Developer Pay-As-You-Go
Free
Usage-based billing ($0.075 per 1,000 characters) with $5 free credit
- Latency
- Sub-100ms time-to-first-audio chunk
- Voice library
- Full access to expressive Sonic voices
Cartesia
● Identity checkedVoice & Audio · Vendor site 2026-10-04
Cartesia is a real-time multimodal intelligence company that builds Sonic, an ultra-fast generative voice model. Sonic produces lifelike speech synthesis with sub-100ms latency, enabling natural, human-speed spoken conversations with AI voice agents.
- Category
- Voice & Audio
- Free access
- $5 in free credits upon registration to test streaming voice APIs.
- API access
- WebSocket and REST streaming APIs designed specifically for real-time voice agents; official Python and TypeScript SDKs.
Is Cartesia right for you?
A good fit for
Engineers and companies building latency-critical conversational voice bots, customer service agents, and interactive gaming NPCs.
Before you choose
Pricing is pay-per-character consumed; high-concurrency production deployments require tier upgrades.
Voice architecture
Cartesia specializes in low-latency voice generation, providing the streaming backbone for the next generation of conversational AI voice agents.
What it can do
Features & capabilities
Unknown is different from unavailable. Each fact carries its own evidence.
| Capability | Value | Evidence | Checked |
|---|---|---|---|
| Sub-100ms First-Chunk Audio | Generates and streams audio packets faster than human conversational response intervals, making AI voice agents feel indistinguishable from human speakers. | Facts sourced | 2026-10-04 |
Understand the total cost
Cartesia pricing & plans
Enterprise
Not listed
Custom volume commitment with dedicated capacity
- Custom voices
- Bespoke custom voice design and fine-tuning
- SLA
- Guaranteed low latency and uptime SLA
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Frequently asked questions
What is Cartesia used for?
Cartesia is a real-time multimodal intelligence company that builds Sonic, an ultra-fast generative voice model. Sonic produces lifelike speech synthesis with sub-100ms latency, enabling natural, human-speed spoken conversations with AI voice agents.
Does Cartesia have a free plan?
$5 in free credits upon registration to test streaming voice APIs.. This record lists ongoing free access; check the plan limits before starting.
How much does Cartesia cost?
No paid monthly price is listed; this record treats the product as free to start. See the plan cards for entitlements, billing commitments and seat minimums.
Can I use Cartesia through an API?
WebSocket and REST streaming APIs designed specifically for real-time voice agents; official Python and TypeScript SDKs.. API access and subscription access may have different terms; consult the linked sources.
What should I check before choosing it?
Pricing is pay-per-character consumed; high-concurrency production deployments require tier upgrades.
Price history
No retained pricing changes yet. A current price alone does not establish a historical trend.
How this profile is supported
Identity and profile
Reviewed vendor source
Read original source ↗Facts apply to the named version and check date. Send a sourced correction if something changed.