Cartesia vs Smallest AI (2026): which should you pick?
As of Nov 12, 2026, Cartesia grades higher than Smallest AI: 2.4 against 1.8 out of 4.0.
Checked Nov 9, 2026 and Nov 12, 2026 · graded Nov 9, 2026 and Nov 12, 2026 by ToolGPA
Cartesia grades higher on value for money, ease of use and platforms. They get the same grade on the free plan and features.
Price, platforms and features side by side. The table says where each price was read and when.
Cartesia
Low-latency speech models and voice agents for developers
Smallest AI
Voice AI models and agents: text to speech, speech to text, calls
Which one is for you
Pick Cartesia if
- Fits if you're building a voice agent or phone bot through an API
- Works for developers who want speech and transcription from one API
Look elsewhere if
- Not for you if you don't write code, or want a voiceover editor or a phone app
- Skip it if you hoped to go live on the free plan, which has no commercial use license
- Tight if you leave overages off, since requests stop when credits run out
- Watch out: overages run $65 per million credits on Pro, and agent calls cost $0.03 a minute plus $0.014 on a Cartesia number
- Pricey if you need a professional voice clone, which starts on the $49 Startup plan
Pick Smallest AI if
- Fits if you prototype voice agents and want to pay by use
- Makes sense if you want speech and speech to text from one vendor
Look elsewhere if
- Not for you if you want a flat monthly price, since there is none
- Tight if you test past the $10 credit, which is one-time
- Watch out: agents cost roughly $0.09 to $0.21 a minute plus a $0.01 a minute hosting fee
- Watch out: HIPAA zero data retention is a $1,000 a month add-on, and SSO and SOC 2 support are Enterprise only
How we grade them
| 2.4GPACartesiaFair | 1.8GPASmallest AIWeak | |
|---|---|---|
| Value for money | BPro is $5 a month for 100,000 credits, about 133 minutes of speech, with a commercial license, instant cloning and $5 of agent calls. An hour a month fits on that plan, which is less than its alternatives charge for the same amount. Overages cost $65 per million credits on Pro. | CNo monthly fee. Lightning v3.1 is about $0.175 per 10,000 characters and Pulse $0.003 a minute, so the bill follows usage and there is no sticker price to rank. |
| Free plan and trial | C20,000 credits a month, about 27 minutes of speech, plus $1 of agent usage. Enough to try it, but there's no commercial use license, so nothing built on it can go live. | C$10 in free credits with full access, once. After that it is pay as you go, and whether a card is needed isn't stated. |
| Features | CStreaming text to speech in dozens of languages, streaming transcription, instant and professional cloning, and voice agents with phone numbers. It does the developer job fully, but that's a narrower job: there's no voiceover editor, as the listing says. | CSpeech, speech to text and hosted agents, with enterprise on-premise. The limits include 15 concurrent TTS streams and a 450M-character monthly cap. |
| Ease of use | CNo store rating on record. It's built for developers: you call it from code with the Python or JavaScript SDK, or try voices in a web playground. Fine if you code, slow going if you don't. | DNo store rating on record. It is a developer platform you call through an API. |
| Platforms and integrations | BWeb and an API with regional endpoints, plus LiveKit, Pipecat, Rasa and Genesys for voice agents, and on-premise setups through sales. No phone or desktop app. | CWeb and an API, with OpenAI listed. No apps. |
| Best for | speech through an API for voice agents | usage-billed voice models and agents |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: Cartesia and Smallest AI. How we grade
Where they differ
- Smallest AI also covers AI agents.
At a glance
| Cartesia | Smallest AI | |
|---|---|---|
| Pricing | Free plan | Free trial |
| Starts at | $5 per month for 100,000 credits, billed monthly | Not published |
| Free plan | 20,000 credits a month (about 27 minutes of text to speech or 1 hour 51 minutes of speech to text) and $1 of voice agent usage. No commercial use license. | None |
| Free trial | None listed | $10 in free credits with full access when you sign up for pay as you go. |
| Web | ||
| Made by | Cartesia | Smallest AI |
| Price read from | cartesia.ai | smallest.ai |
| Checked | Nov 9, 2026 | Nov 12, 2026 |
Worth knowing
Cartesia
- Cartesia is a developer platform: you use it through the API or a web playground, and there is no voiceover editor or mobile app.
- The Free plan has no commercial use license; it starts on Pro, which also adds instant cloning. Professional cloning needs Startup or above.
- Paid plans can go past their credits at $65 per million on Pro, $45 on Startup and $38 on Scale; with overages off, requests are blocked.
- Voice agent calls cost $0.03 a minute from the plan's prepaid dollars, plus $0.014 a minute on a Cartesia phone number.
Smallest AI
- Pay as you go has no monthly fee: about $0.175 per 10,000 characters for Lightning v3.1 ($0.195 for Pro) and $0.003 a minute for Pulse.
- Voice agents cost roughly $0.09 to $0.21 a minute depending on the models chosen, plus a $0.01 a minute hosting fee.
- Pay-as-you-go limits include 15 concurrent TTS streams, 100 TTS requests per minute and a 450M characters monthly cap.
- HIPAA zero data retention is a $1,000 a month add-on, and SOC 2 compliance support and SSO are Enterprise only.
Key features
Cartesia
- Sonic text to speech
- A streaming text-to-speech model built for live conversation, with dozens of languages and regional accents. One minute of audio uses about 750 to 800 credits.
- Ink speech to text
- A streaming transcription model with its own concurrency pool, so heavy transcription does not slow text to speech.
- Voice cloning
- Instant clones from 10 seconds of audio start on Pro; Professional clones start on Startup. Cartesia says to clone only your own voice or one you have explicit permission to use.
- Managed Agents
- Build voice agents that answer and make phone calls, with Cartesia-provided phone numbers, from 1 on Free to 10 on Scale.
- Deployment options
- Call the models through regional API endpoints with Python and JavaScript SDKs, or arrange on-premise, private cloud or on-device deployment with sales.
Smallest AI
- Lightning text to speech
- The Lightning v3.1 model lists sub-100 ms time to first audio, automatic switching between 14+ languages and 44.1 kHz output.
- Voice cloning
- The model page says a voice can be cloned from 5 seconds of audio; the pay-as-you-go comparison table lists voice cloning as not included and custom on Enterprise.
- Pulse speech to text
- Batch and real-time transcription with speaker identification, timestamps and sensitive-data protection, listed at a 5.42% word error rate.
- Hydra speech to speech
- A full-duplex speech-to-speech model that is in beta and available on request.
- Voice agents
- Build agents that run calls and campaigns, with a web widget, phone numbers at $10 a month and post-call analytics.
Plans
Cartesia
Free$0
20,000 credits a month, about 27 minutes of text to speech, plus $1 of prepaid agent usage. Not licensed for commercial use.
Pro$5
per month for 100,000 credits, billed monthly
About 133 minutes of text to speech a month, $5 of agent usage, a commercial use license and instant voice cloning.
Startup$49
per month for 1.25M credits, billed monthly
About 1,667 minutes of text to speech a month, $49 of agent usage and 2 Professional Voice Clone slots.
Scale$299
per month for 8M credits, billed monthly
About 10,667 minutes of text to speech a month, $299 of agent usage, 4 Professional Voice Clone slots, priority support and higher concurrency.
EnterpriseCustom
Volume pricing, custom concurrency, DPAs and BAAs, SSO, a shared Slack channel and on-premise or private cloud deployment.
Smallest AI
EnterpriseCustom
Dedicated infrastructure, a 99.99% uptime SLA, forward deployed engineers, SSO, SOC 2 support, on-premise deployment and custom concurrency. Sold through sales.
Ways to pay less
Cartesia
- Startups
Startups Grant: 12 months of credits
Startups at any stage can apply for 12 months of Scale-level usage: 8 million credits a month plus $299 a month for Managed Agents. Students are considered case by case.
Smallest AI
No public discounts listed.
Common questions
Which is cheaper, Cartesia or Smallest AI?
As of Nov 12, 2026, Cartesia starts at $5 per month for 100,000 credits, billed monthly, and Smallest AI publishes no starting price.
Which has a free plan, Cartesia or Smallest AI?
As of Nov 12, 2026, only Cartesia has a free plan. Smallest AI does not, though it has a free trial.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.