Gladia vs. AssemblyAI

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

Industry-leading accuracy on real-world audio—accents, noise, and technical terms
Lower pay-as-you-go pricing with no spend minimums
Production Voice AI from a single API: models, intelligence, deployment

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Universal-3 Pro

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At a glance: Gladia vs. AssemblyAI

Model

AssemblyAI Universal-3 Pro

Gladia Solaria

Accuracy on real-world audio

Industry-leading

~94% (self-reported)

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

$0.21 / hour

$0.61 / hour

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

From $0.15 / hour

$0.75 / hour

Free tier

$50 in free credits

10 hours / month

No spend minimums for best pricing

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Apply any LLM to transcripts (LLM Gateway)

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BAA available

EU data residency

Go beyond transcription with Assembly's full Voice AI Infrastructure

Best-in-Class Accuracy

Universal-3 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 outgrow Gladia?

Switch to higher accuracy and lower pay-as-you-go pricing—with no contracts or spend minimums.

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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 Pro records a 4.50% average word error rate versus 6.47% for Gladia, and it leads on speaker diarization (33.34% vs 44.04% cpWER). Gladia is strong on multilingual breadth and real-time code-switching across 100+ languages, so 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 $0.61 and $0.75 for Gladia’s pay-as-you-go plan. AssemblyAI includes $50 in free credits and has no spend minimums, while Gladia’s lowest rates require a committed-volume plan.
: AssemblyAI is powered by Universal-3 Pro, a speech model built and trained in-house for Voice AI. Gladia’s current model, Solaria, is a proprietary universal model with 100+ language support, with diarization built on pyannote.
: Yes. AssemblyAI’s Universal Streaming delivers around 300ms latency with streaming speaker diarization and native code-switching, and supports 99 languages for pre-recorded transcription. Gladia supports 100+ languages including real-time multilingual switching, so if broad real-time language coverage is your priority, evaluate both.
: 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 dedicated Gladia-to-AssemblyAI migration guide, and the API maps closely to Gladia’s, so most teams switch with minimal code changes. SDKs are available in Python, TypeScript, Go, Java, and Ruby.