Cartesia Freemium
Cartesia provides text-to-speech (Sonic), speech-to-text (Ink) and voice agent APIs for developers, with voice cloning on paid plans. Free plan has 20K credits a month; Pro is $5 a month.
AI Tool Profile
AssemblyAI
AssemblyAI provides speech-to-text and voice agent APIs for developers, with pre-recorded and real-time transcription in 99 languages. Free tier covers up to 185 hours of pre-recorded audio; pay as you go from $0.15 per hour.
Description of AssemblyAI
AssemblyAI is a voice AI company that sells its technology as APIs for developers rather than as an app for end users. Its site groups the products into transcription, understanding and interaction. Transcription covers pre-recorded, real-time and synchronous speech-to-text APIs. Understanding covers a Speech Understanding API, guardrails and an LLM Gateway. Interaction covers a Voice Agent API and a Dictation API, with a text-to-speech API listed as coming soon.
The site names English, Spanish, Portuguese, French, German, Russian, Hindi, Dutch, Japanese and Italian, and says 99 languages are supported in total. A self-hosted option is listed for teams that need audio to stay inside their own network. The home page shows customer logos such as Zoom and Fireflies and links to a partners page, but it does not list integrations.
Pricing is pay as you go and billed monthly on actual use, with no minimum commitment. Rates are per hour of audio: pre-recorded Universal-3.5 Pro is $0.21 and Universal-2 is $0.15; streaming Universal-Streaming is $0.15. Add-ons such as speaker diarization ($0.02 per hour pre-recorded) are billed on top. The Voice Agent API is $4.50 per hour, or $0.075 per minute. New accounts can start with no card and get up to 185 hours of pre-recorded transcription and 333 hours of streaming. Custom plans are available for higher limits.
The security page describes a SOC 2 Type 2 report and a signed business associate agreement option, and says data sent to EU servers is not used for training.
Features of AssemblyAI
- Pre-recorded, real-time and synchronous speech-to-text APIs covering 99 languages.
- Speech Understanding, guardrails, LLM Gateway and Voice Agent APIs, plus a self-hosted option.
- Pay-as-you-go pricing per hour of audio with a no-card free tier of up to 185 hours.
Frequently asked questions
Is there a free tier?
Yes. No credit card is needed. The free tier covers up to 185 hours of pre-recorded transcription and up to 333 hours of streaming.
How is AssemblyAI priced?
Pay as you go per hour of audio, for example $0.15 for Universal-2 and $0.21 for Universal-3.5 Pro pre-recorded. Add-ons cost extra.
Is it an app for non-developers?
No. It is an API platform for builders, so you need a developer to integrate it.
Website: https://www.assemblyai.com/
Company: AssemblyAI, Inc.
Key facts
Developer API for speech-to-text and voice agents. Pay as you go from $0.15/hour with a no-card free tier of 185 hours. Needs engineering work; not an end-user transcription app.
| Pricing model | Usage-based |
|---|---|
| Free tier | Yes · Up to 185 hours pre-recorded and 333 hours streaming; no credit card |
| Starting price | Not verified |
| Data residency | Multiple regions — The security page says data sent to its EU servers is never used for training. |
| Compliance (as stated by vendor) | SOC 2 Type 2 (claimed), HIPAA (BAA available) (claimed) |
| Integrations | Not verified |
| Public API | Yes |
| Self-hostable | Yes |
| Official site | Not verified |
| Can a general AI assistant replace it? | A general LLM cannot transcribe audio at scale or in real time; use a speech API when you must process many hours of audio. |
| Last verified | 2026-10-10 by editor |
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MacWhisper Freemium
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Update history
- 2026-10-10 · ai alternative note updated (editor)
- 2026-10-10 · editor verdict updated (editor)
- 2026-10-10 · self hostable updated (editor)
- 2026-10-10 · api available updated (editor)
- 2026-10-10 · compliance updated (editor)
- 2026-10-10 · data residency note updated (editor)
- 2026-10-10 · data residency updated (editor)
- 2026-10-10 · pricing page url updated (editor)
- 2026-10-10 · free tier updated (editor)
- 2026-10-10 · pricing model updated (editor)
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