What is async speech-to-text API?

Async speech-to-text is an API that transcribes pre-recorded audio or video files, returning a complete, accurate transcript once processing finishes. It's the right choice for recordings like meetings, podcasts, and support tickets, where you don't need word-by-word results in real time.

How accurate is Gladia's speech-to-text API?

Gladia's both models rank #1 on real-life conversational speech benchmarks, including real customer recordings and noisy, overlapping audio. Solaria-1 also delivers 3x lower diarization errors than other vendors, so speaker labels stay accurate even in multi-speaker calls.

Does Gladia's async API support multiple languages in the same audio file?

Yes. Gladia's async API supports code-switching, detecting and transcribing multiple languages within the same audio file. Solaria-1 covers 100+ languages, with automatic language detection built in, while Solaria-3 is optimized for the highest accuracy on core European languages.

Does the async API include speaker diarization?

Yes, speaker diarization is built into Gladia's async transcription, automatically labeling who said what. Powered by an industry standard pyannote Precision 2 model, Gladia's speaker diarization is #1 in the market according to the open STT benchmark, producing 3x fewer errors than other vendors, which is critical for accurate meeting summaries, call QA, and conversation intelligence.

How does Gladia avoid hallucinations in transcripts?

Gladia's models are trained and benchmarked specifically on real, noisy conversational audio rather than clean read-speech, which reduces the model's tendency to invent words or phrases that were never spoken. This matters most for downstream uses like AI meeting summaries and compliance review, where invented details can't be tolerated.

Is Gladia's async transcription API compliant for regulated industries?

Yes, Gladia is SOC 2 Type 2, HIPAA, GDPR, and ISO 27001 compliant, with data residency options in both the US and EU. Regulated industries can keep audio and transcripts within their required jurisdiction. On-premise deployment is also available for both Solaria-3 and Solaria-1 for teams that need full infrastructure control.

How much does Gladia's async speech-to-text cost?

Gladia's async transcription starts at $0.61/hour on the pay-as-you-go Starter plan, with 10 hours included free every month. Growth plan pricing drops as low as $0.20/hour — up to 67% less than Starter — and Enterprise offers custom, debundled pricing with fine-tuned models.

Can Gladia's be integrated with LLMs?

Yes, Gladia's transcripts are built to feed directly into LLM workflows. For instance, with Audio-to-LLM, you send raw audio in a single API call and get back both the transcript and LLM-analyzed output (summaries, extracted fields, action items) through one webhook, no separate orchestration required. Because Gladia's models prevent hallucinated text, that output is reliable enough to pass straight into your LLM workflow without manual cleanup first.

Gladia | Async Speech-to-Text API

async

Transcription for pre-recorded audio and video in 100+ languages, with industry-leading speaker diarization and automatic language detection. Gladia holds up where most models fall apart: noisy recordings, crosstalk, heavy accents, and speakers who switch languages mid-sentence.

Get €50 in transcription credits. No expiry.

On real-life speech

Best accuracy on conversational audio benchmarks.

Speaker diarization

Most accurate in the market.

100+

Languages covered

Auto-detected, you skip the setup.

Fewer errors than any other model

Gladia's Solaria models outperform every provider on Switchboard, the toughest conversational benchmark. Our benchmark methodology is open-source, so you can reproduce the results.

Compare models Compare models

33.9%

Solaria-3

37.3%

Solaria-1

42.3%

AssemblyAI

46%

Speechmatics

48.1%

Mistral

49.8%

Deepgram

55.2%

ElevenLabs

ACCURACY

The most accurate speech-to-text API

Our Solaria-3 leads on European business audio; Solaria-1 maximizes coverage across 100+ languages. Both benchmarked on real customer recordings.

#1 on Switchboard, the toughest conversational benchmark
Best-in-class on real-world customer audio
Most accurate speaker diarization in the market
Custom vocabulary for product names, acronyms, and domain-specific terms

Accurate async transcription with speaker diarization and custom vocabulary

MULTILINGUAL

Works in any language

Gladia covers languages no other provider transcribes, and handles mid-sentence language switches without any manual configuration.

100+ languages, so no call falls outside your coverage
Auto language detection, no config needed
Translation to target languages as a built-in output
Broad dialect and accent coverage

Multilingual transcription and translation across 100+ languages

COMPLIANCE

Enterprise-grade security and compliance

Sensitive audio needs more than a privacy policy. Gladia is fully compliant with requirements that matter in regulated industries.

SOC 2 Type 2, HIPAA, GDPR, ISO 27001 certified
EU and US data residency options
On-premise deployment for both Solaria-3 and Solaria-1
Your data is never used to train models on paid plans

Enterprise security certifications including GDPR, SOC2, and HIPAA

Everything you need, already built in

All you need to turn raw audio into accurate data, without stitching together separate tools.

Speaker diarization

Automatically detect and label who said what in multi-speaker audio, with 3x fewer errors than other vendors.

Learn more

Custom vocabulary

Boost recognition accuracy for product names, acronyms, and domain-specific terms with keyterm prompting.

Learn more

Audio-to-LLM

Turn audio into structured insights, including summaries and action items, in a single API call, with access to 400+ LLM models.

Learn more

Check the audio-intelligence suite Check the audio-intelligence suite

Match the model for your workflow

Solaria-3 and Solaria-1 are built for different jobs:
Solaria-3 for the highest accuracy on European and English audio. Solaria-1 for the broadest coverage.

Solaria-3

Highest accuracy on European real-world audio

#1 on European business audio and conversational speech
Optimized for EN, FR, DE, ES, IT
#1 on English production audio

Learn more

Solaria-1

Maximum language coverage across any domain

The most multilingual model: 100+ languages
3x lower diarization errors than other vendors
Code-switching, handled natively

Learn more

We are 100% benchmark and evaluation driven. Gladia was one of the best providers selected on merit to transcribe user videos, especially for non-English languages. Their reactive customer support and data compliance make their offer really compelling.

Kojo Hinson Group Engineering Manager

USE CASES

Built for real enterprise use cases

Teams use Gladia's async API to turn raw audio into accurate, structured, and speaker-labeled data they can trust.

Meeting assistants

Accurate, speaker-labeled transcription that powers reliable AI summaries, action items, and CRM sync, without the model inventing details that were never said.

Learn more

Contact centers (CCaaS)

Transcribe and analyze recorded calls at scale for QA, compliance review, and agent coaching, with the multilingual coverage global support teams need.

Learn more

Sales enablement

Turn recorded sales calls into searchable, speaker-tagged transcripts that feed conversation intelligence and CRM workflows.

Learn more

Media & content

Generate accurate, time-stamped subtitles and transcripts for video and podcast content, with support for multi-channel audio.

Learn more

Compare pricing

Pay only for the audio you transcribe, with pricing that drops automatically as volume grows.

Starter

Flexible pay-as-you-go for moderate audio volumes. Get started immediately.

Async at $0.61/hr

Real-time at $0.75/hr

What's included
100+ languages supported
Speaker diarization
Word-level timestamps
Community support

Growth

Lower unit pricing for fast-growing teams. Commit upfront to unlock savings.

Async as low as $0.20/hr

Real-time as low as $0.25/hr

What's included
Everything in Starter
Best WER on the market
Custom vocabulary & prompts
Priority support SLA
Volume discounts

Enterprise

Annual plan with custom models, fine-tuning, debundled pricing, and more.

Custom

tailored to your audio volume and SLA requirements

What's included
Everything in Growth
Dedicated infrastructure
GDPR & SOC 2 compliance support
99.9% uptime SLA
Named account manager
On-prem deployment available

Explore the pricing Explore the pricing

FAQs

Async speech-to-text is an API that transcribes pre-recorded audio or video files, returning a complete, accurate transcript once processing finishes. It's the right choice for recordings like meetings, podcasts, and support tickets, where you don't need word-by-word results in real time.
Gladia's both models rank #1 on real-life conversational speech benchmarks, including real customer recordings and noisy, overlapping audio. Solaria-1 also delivers 3x lower diarization errors than other vendors, so speaker labels stay accurate even in multi-speaker calls.
Yes. Gladia's async API supports code-switching, detecting and transcribing multiple languages within the same audio file. Solaria-1 covers 100+ languages, with automatic language detection built in, while Solaria-3 is optimized for the highest accuracy on core European languages.
Yes, speaker diarization is built into Gladia's async transcription, automatically labeling who said what. Powered by an industry standard pyannote Precision 2 model, Gladia's speaker diarization is #1 in the market according to the open STT benchmark, producing 3x fewer errors than other vendors, which is critical for accurate meeting summaries, call QA, and conversation intelligence.
Gladia's models are trained and benchmarked specifically on real, noisy conversational audio rather than clean read-speech, which reduces the model's tendency to invent words or phrases that were never spoken. This matters most for downstream uses like AI meeting summaries and compliance review, where invented details can't be tolerated.
Yes, Gladia is SOC 2 Type 2, HIPAA, GDPR, and ISO 27001 compliant, with data residency options in both the US and EU. Regulated industries can keep audio and transcripts within their required jurisdiction. On-premise deployment is also available for both Solaria-3 and Solaria-1 for teams that need full infrastructure control.
Gladia's async transcription starts at $0.61/hour on the pay-as-you-go Starter plan, with 10 hours included free every month. Growth plan pricing drops as low as $0.20/hour — up to 67% less than Starter — and Enterprise offers custom, debundled pricing with fine-tuned models.
Yes, Gladia's transcripts are built to feed directly into LLM workflows. For instance, with Audio-to-LLM, you send raw audio in a single API call and get back both the transcript and LLM-analyzed output (summaries, extracted fields, action items) through one webhook, no separate orchestration required. Because Gladia's models prevent hallucinated text, that output is reliable enough to pass straight into your LLM workflow without manual cleanup first.

Async speech-to-text API

On real-life speech

Speaker diarization

Languages covered

Fewer errors than any other model

The most accurate speech-to-text API

Works in any language

Enterprise-grade security and compliance

Everything you need, already built in

Speaker diarization

Custom vocabulary

Audio-to-LLM

Match the model for your workflow

Solaria-3

Solaria-1

Built for real enterprise use cases

Meeting assistants

Contact centers (CCaaS)

Sales enablement

Media & content

Compare pricing

Starter

Growth

Enterprise

FAQs

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