The short version
Choose AssemblyAI when you want a broad catalog of speech-understanding add-ons and generous one-time evaluation credit. Choose Omi when the core job is medical transcription and you want the full clinical feature set, a recurring free allowance and a self-serve BAA without assembling a feature bill.
Accuracy uses Omi's sealed clinical benchmark. AssemblyAI pricing shown as Universal-3.5 Pro at $0.21/hr plus the published $0.15/hr Medical Mode add-on; optional features can change the total. Checked 29 August 2026.
Medical accuracy
Omi leads the evaluated AssemblyAI medical configuration on medical-term error, drug-name error and dosage F1. The dosage gap is the most meaningful: it measures aligned number-and-unit events separately rather than allowing common words to dominate the score.
Run an acceptance set for your specialties. An ambient psychiatry product, dental dictation tool and medication-reconciliation workflow can fail in different ways even when a global WER looks similar.
The real medical price
AssemblyAI's base rate is only the first line. Its public price list currently shows Universal-3.5 Pro at $0.21 per hour, Medical Mode at another $0.15 per hour, async diarization at $0.02 and keyterm prompting at $0.05. Use only the features you need, but include them when comparing a medical workflow.
Omi's $0.29 batch rate includes medical vocabulary, speaker labels and timestamps. Live is $0.45 and includes a fast draft, confirmed text and a batch-quality final in the same session.
Free tier and conversion
AssemblyAI's one-time credit is larger for a concentrated benchmark. Omi's 25 hours recur every month and stay included after you add a card. That recurring lane is designed for clinician-built tools and small healthcare projects that should remain dependable without becoming a billing surprise.
Compliance path
Both vendors provide BAA paths. Omi makes the BAA and DPA self-service from Builder, before payment. Whichever provider you choose, sign the agreement for the exact product before sending PHI and review the complete data path—not only the speech endpoint.
Sources and methodology
Review the full Omi benchmark, AssemblyAI pricing and AssemblyAI medical solution. Prices and product eligibility change; verify the current contract.