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.
O
AI Tool Profile
OpenAI API
The OpenAI API is OpenAI's developer platform for text, image and audio models, billed per use and separate from ChatGPT. Speech-to-text is listed from $0.0045 per minute; no free credit is mentioned on the pricing page.
Description of OpenAI API
The OpenAI API platform is where developers use OpenAI models inside their own software. It is separate from ChatGPT: the pricing page states that API billing does not come with ChatGPT Plus, Business, Enterprise or Edu subscriptions, and that usage in the Playground is billed at normal API rates. The platform home page itself shows little beyond its title, so product detail here comes from the pricing page.
The model list there includes text models in three tiers called GPT-5.6 Sol, Terra and Luna, an image model called GPT-Image-2, realtime voice models, and audio transcription and translation models. For transcription, GPT-Transcribe is listed at $0.0045 per minute, GPT-Live-Transcribe at $0.017 per minute and GPT-Realtime-Translate at $0.034 per minute. GPT-Realtime-2.1 is billed per token for audio input and output. The page we read did not show text-to-speech or Whisper prices, so check the audio section of the full pricing page before budgeting for voice generation.
Pricing is pay as you go. Batch processing is 50% cheaper for work that can wait up to 24 hours, flex processing trades speed for lower cost, and data residency adds 10% to the standard rates. Enterprise options such as Scale Tier and reserved capacity are sold through sales. No free credit is mentioned on the pricing page.
This is a building block, not a finished transcription or voiceover app. You or a developer must write code or use a connector to feed audio in and handle the output.
Features of OpenAI API
- Pay-per-use access to OpenAI text, image, realtime voice and transcription models through an API.
- Audio transcription priced per minute, from $0.0045 for GPT-Transcribe, plus a realtime translation model.
- Batch (50% off), flex processing, regional data residency at +10% and enterprise capacity options.
Frequently asked questions
Is the OpenAI API free?
The pricing page mentions no free credit. Usage is billed at API rates, and API billing is separate from ChatGPT subscriptions.
How much does transcription cost?
GPT-Transcribe is listed at $0.0045 per minute and GPT-Live-Transcribe at $0.017 per minute. Check the full audio pricing for other models.
Is it the same as ChatGPT?
No. The API is a developer platform with separate billing; ChatGPT plans do not include API usage.
Website: https://platform.openai.com/
Company: OpenAI
Key facts
Pay-per-use developer platform for text, image and audio models, billed apart from ChatGPT. Transcription from $0.0045/min; text-to-speech prices not read. Needs developer effort.
| Pricing model | Usage-based |
|---|---|
| Free tier | No free plan |
| Starting price | Not verified |
| Data residency | Not verified |
| Compliance (as stated by vendor) | Not verified |
| Integrations | Not verified |
| Public API | Yes |
| Self-hostable | Not verified |
| Official site | Not verified |
| Can a general AI assistant replace it? | ChatGPT cannot process audio in bulk by itself; the API suits batch transcription or building voice features into an app. |
| Last verified | 2026-10-10 by editor |
Alternatives & Similar Tools
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Amazon Polly Freemium
Amazon Polly is the AWS text-to-speech service with Standard, Neural, Long-Form and Generative voices, billed per character. The free tier covers 5 million Standard characters a month; Neural voices cost $16 per million characters.
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Azure Speech Freemium
Azure Speech is Microsoft's cloud speech service for text to speech, speech to text, translation and voice agents, now sold as part of Microsoft Foundry. The free F0 tier includes 0.5 million neural text-to-speech characters a month.
WellSaid Freemium
WellSaid is an AI text-to-speech platform for voiceovers built with professional voice actors, with an API and 50+ languages and accents. The free trial gives 3 minutes a month; Starter is $19 a month.
Typecast Freemium
Typecast is an AI voice generator with 700+ voices, voice cloning, a web studio, iOS and Android apps and an API. The Free plan gives about 5 minutes of lifetime downloads; Basic is $5 a month.
Update history
- 2026-10-10 · ai alternative note updated (editor)
- 2026-10-10 · editor verdict updated (editor)
- 2026-10-10 · api available 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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