The short version
Choose OpenAI when transcription belongs inside a broader OpenAI application and you want one vendor for speech, language and realtime AI. Choose Omi when the transcript itself is a medical product dependency and you want domain-specific measurements, recurring free hours, an included clinical feature set and an open local model.
Accuracy uses the OpenAI row evaluated on Omi's sealed clinical benchmark. OpenAI's model catalog evolves quickly; the current API now includes multiple file, realtime and diarized transcription options. Checked 29 August 2026.
Purpose-built versus general
OpenAI's transcription models are general multilingual speech models. They can accept prompt context and now include diarized transcription options. Omi's hosted model and benchmark are centred on consultations, dictation, medical terms, drug names and dosages.
That focus shows in the evaluated result: Omi leads the tested OpenAI transcription row on all four published clinical measures. As always, a public benchmark should be followed by testing on your own specialties and acoustics.
Product architecture
If your application already uses OpenAI for reasoning, using its transcription endpoint can reduce vendor count. But speech and reasoning have different failure modes. A modular speech layer lets you select and monitor the transcript independently before it reaches an LLM.
Omi is OpenAI-compatible at the transcription interface, so builders can use a familiar request shape while keeping the medical speech layer specialised.
BAA and retention
OpenAI says an enterprise agreement is not required for an API BAA, but requests are reviewed and the account must be configured for eligible services and modified retention before PHI is processed. Its API business data is not used for training by default.
Omi provides a self-serve BAA and DPA from Builder, processes hosted API data in the EU, lets a project choose 1–72 hour result retention and never uses customer audio or transcripts for model training. Review both current contracts for the exact endpoint and region you plan to use.
Pricing
Omi expresses speech cost in audio-hours: $0.29 batch and $0.45 live after 25 recurring free hours. OpenAI's newer transcription models are token-priced, so the effective cost depends on audio and output usage. Estimate from representative files rather than converting a marketing number in isolation.
Sources and methodology
Review the full Omi benchmark, OpenAI transcription model page, audio API reference and OpenAI API BAA guidance.