AWS Transcribe vs. AssemblyAI

Learn why developers choose AssemblyAI to build powerful Voice AI apps that exceed industry standards:

Much lower word error rate on real-world audio (4.5% vs 12.9%)
Faster streaming—335ms median turnaround vs over 1.1s
Lower pay-as-you-go pricing with no spend minimums

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Universal-3.5 Pro

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At a glance: AWS Transcribe vs. AssemblyAI

Model

AssemblyAI Universal-3.5 Pro

AWS Transcribe

Word error rate (average)

4.5%

12.9%

Missed entity rate

7.5%

20.76%

Streaming latency (median time-to-complete-turn)

335 ms

1,136 ms

Pre-recorded pricing (pay-as-you-go)

$0.21 / hour

$0.36 / hour

Real-time pricing (pay-as-you-go)

From $0.15 / hour

$0.60 / hour

Free tier

$50 in free credits

60 min / month for 12 months

Unlimited concurrency

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Apply any LLM to transcripts (LLM Gateway)

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BAA available

Go beyond transcription with Assembly's full Voice AI Infrastructure

Best-in-Class Accuracy

Universal-3.5 Pro is the most accurate, controllable model on the market, with industry-leading accuracy on real-world audio—noisy environments, accents, and technical vocabulary—plus best-in-class recognition of names, emails, and numbers.

Realtime Streaming

Ultra-low-latency streaming transcription (~300ms) purpose-built for voice agents, with immutable transcripts and native code-switching.

Speaker Diarization

Built-in speaker labels on pre-recorded and streaming audio, with each word in the transcript associated to its speaker.

Lower, Usage-Based Pricing

Pay only for what you use—$0.21/hr batch and real-time from $0.15/hr—with $50 in free credits and no minimum commitments or contracts.

LLM Gateway

Route 25+ leading LLMs through one OpenAI-compatible API to build Q&A, summaries, extraction, and agentic workflows on your transcripts.

Speech Understanding

Layer summarization, sentiment analysis, topic detection, and auto chapters on top of every transcript.

PII Redaction & BAA

Detect and redact PII from transcripts and audio, and sign a BAA for apps that process PHI.

Proven Reliability and Security

Deploy on infrastructure that processes millions of hours daily, with 99.9% uptime, unlimited concurrency, and SOC 2 Type 2, ISO 27001, PCI DSS, and GDPR.

Start building

Get your free API key and ship your first transcript in minutes—no commitments or minimums.

Ready to move beyond AWS Transcribe?

Switch to higher accuracy and lower pay-as-you-go pricing—no contracts, no spend minimums, and no job-polling boilerplate.

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Investments in STT improvements always pay for themselves, since it is such a critical building block of the voice pipeline.

Lindsay Liu, Co-Founder & CEO at Super

Playground

We're not playing around—but you can

Test our best-in-class speech-to-text and voice agent models in our no-code playground.

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Frequently asked questions

: AssemblyAI is more accurate in AssemblyAI’s benchmarks (assemblyai.com/benchmarks): Universal-3.5 Pro records a 4.5% average word error rate versus 12.9% for AWS Transcribe, and a 7.5% missed entity rate versus 20.76%—the entities like names, dates, and account numbers that matter most in downstream workflows. Always test both on your own audio.
: Yes. AssemblyAI’s pre-recorded transcription is $0.21 per hour and real-time starts at $0.15 per hour, versus $0.36 per hour for AWS Transcribe batch and $0.60 per hour for streaming (US East pricing). AssemblyAI includes $50 in free credits with no spend minimums, while AWS’s free tier is 60 minutes per month for the first 12 months.
: AssemblyAI. In the Pipecat STT Benchmark cited on assemblyai.com/benchmarks, Universal-3.5 Pro Realtime returns final transcripts in a median of 335ms after the speaker stops talking, versus 1,136ms for AWS Transcribe—a meaningful difference for voice agents and live captioning.
: No. AssemblyAI is a managed API that works alongside your existing AWS infrastructure—you can keep audio in S3 and submit publicly accessible or presigned URLs for transcription, then store results wherever your stack lives.
: Yes. AssemblyAI offers a Business Associate Addendum (BAA) and is certified for SOC 2 Type 2, ISO 27001, PCI DSS, and GDPR, so you can build healthcare and other regulated workloads.
: Yes. AssemblyAI publishes a step-by-step AWS Transcribe-to-AssemblyAI migration guide with side-by-side code, and SDKs are available in Python, TypeScript, Go, Java, and Ruby. Most teams switch with minimal code changes—and skip the job-polling boilerplate AWS requires.