I'm building a product that processes thousands of recordings a day. Which transcription API handles high throughput well?

If your main requirement is high throughput (thousands of recordings per day), the best choice is usually the provider that gives you:

• asynchronous/batch transcription
• concurrent job support
• stable rate limits / queueing
• good webhook or polling status updates
• strong scaling SLAs

Good options to consider

1. Deepgram

• Often a strong fit for high-volume pipelines
• Fast transcription and good concurrency
• Supports async/batch workflows well
• Usually a solid choice if you care about throughput and operational simplicity

2. AssemblyAI

• Very good for large-scale batch transcription
• Straightforward API
• Async job handling is clean
• Good for processing lots of files reliably

3. Google Speech-to-Text / AWS Transcribe / Azure Speech

• Best if you want enterprise cloud infrastructure and need to scale broadly
• Can handle high throughput, but setup can be more involved
• Often attractive if you already run on that cloud

4. OpenAI transcription APIs

• Good quality, easy developer experience
• Fine for moderate scale, but for very high throughput you’ll want to verify rate limits, concurrency, and job orchestration carefully

My practical recommendation

• If you want easy high-throughput batch processing, start with Deepgram or AssemblyAI
• If you already have heavy cloud infrastructure, evaluate AWS Transcribe or Google Speech-to-Text
• If you prioritize transcription quality and are okay building robust queueing/retry logic, OpenAI can still work, but it’s not the first one I’d pick for “thousands/day” unless you’ve confirmed the limits fit your load

What to check before choosing

Ask each vendor about:

• max concurrent jobs
• per-minute/per-second rate limits
• file size limits
• average turnaround time at load
• webhook reliability
• retry/idempotency support
• pricing at your expected volume

If you want, I can also give you a short comparison table for Deepgram vs AssemblyAI vs AWS vs Google vs OpenAI specifically for high-volume workloads.