AssemblyAI vs OpenAI Moderation API
AssemblyAI
assemblyai.comOpenAI Moderation API
developers.openai.comSide by side
| Figure | AssemblyAI | OpenAI Moderation API |
|---|---|---|
| Price from | $0.15/mo | $15/mo |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | — |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 13 | 2 |
| Spec score · Speech-to-Text Software | 8.8 (#10) | 6.3 (#31) |
Plans
AssemblyAI
- Free creditsFree
- Pay as you go — Universal-2$0.15 a month
- Pay as you go — Universal-3.5 Pro$0.21 a month
- Pay as you go — Universal-Streaming$0.15 a month
- Pay as you go — Universal-3.5 Pro Realtime$0.45 a month
- Free tierFree
- Universal-2$0.15 a month
- Universal-Streaming$0.15 a month
- Universal-Streaming Multilingual$0.15 a month
- Universal-3.5 Pro$0.21 a month
In their own words
AssemblyAI
AssemblyAI provides Voice AI models and APIs for speech-to-text, speech understanding, and voice applications. Its Speech Understanding API can identify and diarize speakers, summarize speech, extract action items and key phrases, detect sentiment, entities, and topics, and handle formatting, language detection, translation, PII redaction, and content moderation. The platform lists support for 99 languages and translation into 86. It offers streaming and voice-agent latency below 300ms and states that it processes more than 800 million API calls per month. Use its managed cloud or self-host models in your own environment; the service also lists API access and integrations including Twilio, Zoom RTMS, Zapier, and LangChain. Security options include TLS 1.2+ in transit, AES-256 at rest, zero data retention, and opting out of model training. A free tier is available. Pay-as-you-go billing is based on usage, with monthly invoices and no minimum commitments. Universal-2 is listed at $0.15 per hour of audio; Universal-3.6 Pro Realtime is $0.45 per hour.
OpenAI Moderation API
OpenAI Moderation API has no write-up on Specifiction yet; its figures are above.