Cartesia
Low-latency Sonic text-to-speech for voice agents, sold as monthly credit plans with tiered overage rates.
Sonic's monthly plans use one credit per character. Overage falls from $65 per million on Pro to $38 on Scale. Unused credits roll over up to twice the monthly allowance. Compare latency and voice quality against lower-priced APIs before committing to a larger plan. We found no documented self-serve EU region.
- Headquarters
- 🇺🇸 United States
- Parent jurisdiction
- 🇺🇸 United States
- EU self-serve plan
- No / not documented
- GDPR DPA
- Yes
- Billing
- subscription
- Free tier
- Free plan: 20K credits/month (~20K characters), no overage.
- Open source
- No
- Website
- cartesia.ai
- Source last checked
- 2026-10-06
- Pricing evidence
- Published rates
Pricing
Calculated from the listed vendor rates; exclusions still apply. How to read these estimates.
| Plan | Base fee / month | 1M additional characters |
|---|---|---|
| Free | $0 | $0 |
| Pro | $5 | $65 |
| Startup | $49 | $45 |
| Scale | $299 | $38 |
Allowances, plan limits & calculation details
Rates are shown at their recorded precision. A zero means no charge in this calculation; the vendor may charge for things we leave out. See the notes for usage assumptions and currency conversions.
Free
- Base fee / month
- $0
- Included characters / month (millions)
- 0.02
- 1M additional characters
- $0
- Modeled plan limits
- ≤ 0.02 characters / month (millions)
Pro
- Base fee / month
- $5
- Included characters / month (millions)
- 0.1
- 1M additional characters
- $65
Startup
- Base fee / month
- $49
- Included characters / month (millions)
- 1.25
- 1M additional characters
- $45
Scale
- Base fee / month
- $299
- Included characters / month (millions)
- 8
- 1M additional characters
- $38
Current model Sonic-3.6; 1 credit = 1 character (750-800 credits per minute of audio). Plans: Free 20K credits, Pro $5 100K, Startup $49 1.25M, Scale $299 8M credits per month; credits are shared with Ink speech-to-text and each plan also includes the same dollar amount of prepaid Managed Agents usage. Paid plans can enable overage at $65 (Pro), $45 (Startup) or $38 (Scale) per 1M credits; unused credits roll over up to 2x the monthly amount. No annual pricing listed. Enterprise: custom volume pricing, BAAs, on-prem/VPC deployment. No EU region documented for self-serve. San Francisco-based; DPA published at cartesia.ai/legal/dpa.
Managed alternatives
At 10M characters / month. Adjust usage and requirements.
Cartesia: $4,500/yr estimated.
- Kokoro-82M on DeepInfra: $74/yr estimated · $4,426/yr bill differencePublished rates
- Speechify API: $1,092/yr estimated · $3,408/yr bill differencePublished rates
- Murf API: $1,200/yr estimated · $3,300/yr bill differencePublished rates
- Azure AI Speech: $1,800/yr estimated · $2,700/yr bill differencePublished rates
- Fish Audio API: $1,800/yr estimated · $2,700/yr bill differencePublished rates
No cheaper managed estimate matches your filters. Adjust your usage or compare with your actual contract bill.
The price difference leaves out migration costs, operating costs and any features you’d need to replace.
Self-hosted options
Operating cost is not estimated. These options are not counted as savings against managed services.
Compare Cartesia
Found a wrong rate or plan restriction? Report a correction with a current source.