Audio tools / Compare
AssemblyAI vs Sonix
Both do 1 of the same audio tools task. Below is what each says about its own limits and pricing, and how each ranks on signals we can measure or quote.
Disclosure: agathox makes some of the tools listed here. They are labelled and scored by the same method as every other tool.
A
AssemblyAI
With AssemblyAI's industry-leading Speech AI models, transcribe speech to text and extract insights from your voice data.
Signals score: 4.2 / 5 · not a hands-on test
Visit www.assemblyai.comB
Sonix
Transcribe audio and video to text in minutes with 99% accuracy. 54+ languages, AI summaries, and speaker detection. Try Sonix free — no credit card required.
Signals score: 4.0 / 5 · not a hands-on test
Visit sonix.aiPricing, limits and privacy
- Free tier
- A: $50 in free credits at signup, no credit card required. Streaming is limited to 5 new streams per minute on the free tier.
- B: Every new account gets a 30-minute free trial of transcription; no credit card required.
- Paid plan
- A: Pay as you go, no subscription tiers listed. Pre-recorded example: $0.21 per hour (Universal-3.5 Pro). Streaming example: $0.45 per hour base (Universal-3.6 Pro Realtime). Text-to-speech: $15 per 1M input characters. Paid raises streaming to 100 new streams per minute. Volume pricing via sales. Currency is shown as $ but not named.
- B: Pay As You Go $10/hr. Core $25/mo or $275/yr (5 hrs/mo). Advanced $50/mo or $550/yr (20 hrs/mo). Pro $80/mo or $880/yr (40 hrs/mo). Enterprise custom. Extra hours on subscriptions $10/hr. Prices in USD.
- Signup
- A: Signup is needed to get the free credits and an API key.
- B: Account needed; the trial starts by creating an account.
- Watermark
- A: Not applicable.
- B: Not stated.
- Where files go
- A: The privacy policy says services are mainly hosted and operated in the United States and data may be transferred to other countries. It does not mention audio and gives no retention period for audio or transcripts; personal data is kept as long as needed for the services or business purposes.
- B: Privacy policy does not name a storage location; it says personal data may be stored outside the EEA/UK. When an account is deleted, media files and transcripts are destroyed, but copies may stay in backups for up to 90 days.
From each tool's own pages, checked 2026-11-01. Prices and limits change; check the tool before you rely on them. Sources are listed on each tool's page.
Compare on a task
Neither tool has been hands-on tested on these tasks yet, and we do not guess. Open a task to see both ranked with every other tool.
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