# Speechmatics vs AssemblyAI: Speech-to-Text Comparison (2026)

Source: https://www.speechmatics.com/how-we-compare/assemblyai-alternative

Speechmatics vs AssemblyAI compared on accuracy, languages, deployment, and pricing. See why enterprises choose Speechmatics for speech-to-text.

## **Speechmatics vs AssemblyAI:** Which Speech-to-Text API Delivers?

See why developers are switching to Speechmatics for superior speech-to-text accuracy, best-in-class speaker diarization, broader language coverage, and flexible deployment options that AssemblyAI cannot match.

- [Get $200 Free Credit](https://www.speechmatics.com#switch200)
- [Contact Sales](https://www.speechmatics.com/speak-to-sales)

Speechmatics named G2 Leader in 2026

- [G2 Easiest to Use – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 Best Support – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 Easiest to Use Small Business – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 Transcription Leader EMEA – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 Transcription Leader Europe – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 Transcription Leader – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 Users Most Likely to Recommend – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 High Performer EMEA – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 High Performer – Summer 2026](https://www.g2.com/products/speechmatics/reviews)
- [G2 High Performer Europe – Summer 2026](https://www.g2.com/products/speechmatics/reviews)

## See how Speechmatics compares vs AssemblyAI on your audio

Choose from live radio, your own voice, or sample audio to see side-by-side comparisons of Speechmatics vs AssemblyAI.

## Why Speechmatics — Why teams evaluate Speechmatics after trying AssemblyAI

### Accuracy — Unmatched real-world accuracy

Speechmatics delivers **industry-leading accuracy in noisy settings**, across diverse accents and dialects. Trained on real-world audio — not just clean recordings.

- [Real-Time, real benefits](https://www.speechmatics.com/languages)

### Languages — Broader language coverage

[**56+ languages**](https://www.speechmatics.com/languages) with a single model, covering all accents and dialects — production-ready real-time transcription for over half the world's population.

- [Languages](https://www.speechmatics.com/languages)

### Deployment & Security — Enterprise-grade flexibility

Mature [**on-premises**](https://docs.speechmatics.com/deployments)**, cloud,** [**on-device**](https://www.speechmatics.com/speech-to-text/on-device)**, and air-gapped** deployments. [**ISO 27001**](https://www.speechmatics.com/security)**, SOC2, HIPAA, and GDPR** compliant to cover all your security needs.

- [Pricing](https://www.speechmatics.com/pricing)

## Feature comparison — Speechmatics vs AssemblyAI: Feature-by-feature comparison

A detailed look at the two platforms across core capabilities, advanced features, and verified public reviews.

| **Feature** | **Speechmatics ⭐** | **AssemblyAI** |
| --- | --- | --- |
| Flagship Model | [Ursa 2 (Enhanced)](https://www.speechmatics.com/company/articles-and-news/ursa-2-elevating-speech-recognition-across-52-languages) | Universal-2 |
| Supported Languages | [56+ languages](https://www.speechmatics.com/languages) | Limited multilingual streaming |
| Accent Coverage | Industry-leading across [56+ languages](https://www.speechmatics.com/languages) | Available, but not a focus |
| Real-Time Transcription | Yes | Yes |
| Batch Transcription | Yes | Yes |
| Noisy Audio Handling | Best-in-class (90% [G2 score](https://www.g2.com/compare_reports/speechmatics-and-assemblyai-speech-to-text-api-spring-2026.embed)) | Below average (80% [G2 score](https://www.g2.com/compare_reports/speechmatics-and-assemblyai-speech-to-text-api-spring-2026.embed)) |
| Latency | Yes Under 500ms | Yes Under 500ms |
| [Speaker Diarization](https://www.speechmatics.com/use-cases/ai-voice-agents) | Yes Included, no extra charge, real-time | Yes Recently launched; channel separation increases cost |
| Custom Dictionary | 1,000 words (included at no extra charge) | 1,000 words |
| Cloud Deployment | Yes | Yes |
| [On-Premises Deployment](https://docs.speechmatics.com/deployments) | Yes | Limited (containers only) |
| On-Device Deployment | Yes | No |
| Air Gapped | Yes | No |
| [ISO 27001 Certified](https://www.speechmatics.com/security) | Yes | Yes |
| SOC2 Type II | Yes | Yes |
| HIPAA Compliant | Yes | Yes |
| GDPR Compliant | Yes | Yes |
|  |  |  |

### Public Reviews - G2 Spring 2026

| **Feature** | **Speechmatics ⭐** | AssemblyAI |
| --- | --- | --- |
| Overall G2 Rating | 4.8 / 5 (57 reviews) | 4.6 / 5 (110 reviews) |
| Ease Of Use | 94% | 90% |
| Quality of Support | 91% | 89% |
| Likelihood to Recommend | 96% | 92% |
| Meets Requirements | 91% | 88% |
| Product Direction (% positive) | 98% | 95% |
| Average Time to ROI | 3 months | 6 months |
| Low-Latency Processing | 93% | 77% |
| Regulatory Compliance | 95% | 80% |
| Multilingual Voice Recognition | 91% | 78% |
| Speaker Differentiation | 88% | 79% |
| Secure Communication | 93% | 81% |
| Software Integration | 92% | 83% |
| Accuracy in Noise Settings | 90% | 80% |
| Sentiment & Tone Analysis | 87% | 74% |
|  |  |  |

**Source:** [_G2 Comparison Report Spring 2026 - Speechmatics vs AssemblyAI_](https://www.g2.com/compare_reports/speechmatics-and-assemblyai-speech-to-text-api-spring-2026.embed)

## Where Speechmatics outperforms AssemblyAI

### Superior real-time accuracy

Consistently outperforms AssemblyAI in real-time transcription accuracy, particularly in **noisy environments** (90% vs 80% on G2), **diverse accents**, and multi-speaker scenarios where clarity matters most. See [how Speechmatics performs on voice agent benchmarks](https://www.speechmatics.com/company/articles-and-news/speed-you-can-trust-the-stt-metrics-that-matter-for-voice-agents).

### Real-time speaker diarization

**Best-in-class speaker diarization** available in real-time at no extra charge. AssemblyAI does not offer speaker diarization in streaming — only in batch — and multi-channel separation increases cost.

### Broader language support

[**56+ languages**](https://www.speechmatics.com/languages) with a single model covering all accents and dialects. AssemblyAI's multilingual streaming was only recently launched with limited language support, scoring just 78% vs Speechmatics' 91% on G2.

### Enterprise-grade deployment

Mature [**on-premises**](https://docs.speechmatics.com/deployments)**,** [**on-device**](https://www.speechmatics.com/speech-to-text/on-device)**, and air-gapped** deployment options. [**ISO 27001 certified**](https://www.speechmatics.com/security), GDPR, HIPAA, SOC2 compliant. AssemblyAI is SaaS-first with on-prem still in beta.

### Faster time to ROI

G2 reviewers report an average **3-month time to ROI** with Speechmatics versus 6 months with AssemblyAI. Combined with a **98% product direction** satisfaction score, Speechmatics is the future-proof choice.

### Transparent, all-inclusive features

**Speaker diarization and custom dictionary included** at no extra charge. AssemblyAI charges add-on fees for features like summarization, PII redaction, and content moderation — costs that add up at scale.

## Limited time offer

### Start building with Speechmatics today

1) 👤 Log in or signup to [the Speechmatics Portal](https://portal.speechmatics.com/settings/billing/overview)

2) 💳 Add a valid payment card (no charge until credit is used)

3) 🔑 Enter your code: **SWITCH200**

4) 🚀 Start building with $200 free credit

- [Activate my credit](https://portal.speechmatics.com/settings/billing/overview)

## Frequently Asked Questions: Speechmatics vs AssemblyAI

### Is Speechmatics more accurate than AssemblyAI?

Yes. Speechmatics consistently outperforms AssemblyAI in real-world transcription accuracy. On G2, Speechmatics scores **90% for accuracy in noisy settings** versus AssemblyAI's 80%, and **94% for environmental noise adaptation** versus 83%. Our [Ursa 2](https://www.speechmatics.com/company/articles-and-news/ursa-2-elevating-speech-recognition-across-52-languages) model is trained on over one million hours of diverse audio data, delivering best-in-class accuracy across accents, dialects, and challenging audio environments.

Here are [recent benchmarks from Daily (Pipecat)](https://www.daily.co/blog/benchmarking-stt-for-voice-agents/), where Speechmatics were recognized as a top-tier provider for real-time voice agents, sitting firmly on the "Pareto frontier" — and see how [Speechmatics integrates with Pipecat](https://docs.speechmatics.com/integrations-and-sdks/pipecat/).

### How many languages does Speechmatics support vs AssemblyAI?

Speechmatics supports [**56+ languages**](https://www.speechmatics.com/languages) with a single model covering all accents and dialects. While AssemblyAI has been expanding its multilingual capabilities, their real-time streaming support was only recently launched with a limited set of European languages (French, Spanish, German, Italian, Portuguese). Speechmatics has production-grade multilingual support across all deployment modes — scoring **91% versus AssemblyAI’s 78%** for multilingual voice recognition on G2. Our new [Melia model](https://www.speechmatics.com/company/articles-and-news/introducing-melia-multilingual-speech-to-text-model) also adds native code-switching across all 56+ supported languages in a single pass.

### Does Speechmatics support real-time speaker diarization?

Yes. Speechmatics offers **best-in-class real-time speaker diarization at no extra charge**. This is a significant differentiator — AssemblyAI does not support speaker diarization in real-time streaming. They require you to use batch processing for diarization, or push users toward multi-channel audio which increases cost. For use cases like [live meeting transcription](https://www.speechmatics.com/use-cases/meeting-platforms), [call centers](https://www.speechmatics.com/use-cases/contact-center-solutions), and [voice agents](https://www.speechmatics.com/use-cases/ai-voice-agents), real-time speaker identification is critical.

### Can Speechmatics be deployed on-premises?

Yes. Speechmatics offers mature, production-ready [**on-premises deployment**](https://docs.speechmatics.com/deployments) alongside cloud, [on-device](https://www.speechmatics.com/speech-to-text/on-device), and fully air-gapped options. This is essential for enterprises in regulated industries like [healthcare](https://www.speechmatics.com/use-cases/medical-transcription), finance, and government. AssemblyAI is primarily a SaaS platform — their on-premises offering was only recently launched in beta with design partners. Speechmatics scores **95% on G2 for regulatory compliance** versus AssemblyAI's 80%.

### How does Speechmatics compare to AssemblyAI on latency?

Speechmatics delivers [**500ms partial transcripts**](https://www.speechmatics.com/company/articles-and-news/speed-you-can-trust-the-stt-metrics-that-matter-for-voice-agents) and sub-1-second final results in real-time streaming. On G2, Speechmatics scores **93% for low-latency processing** versus AssemblyAI's 77% — a 16-percentage-point gap. For latency-sensitive applications like voice agents, live captioning, and real-time analytics, this difference is significant.

### Is Speechmatics HIPAA and ISO 27001 compliant?

Yes. Speechmatics holds [**ISO 27001 certification**](https://www.speechmatics.com/security)**, SOC2 Type II, HIPAA compliance, and full GDPR compliance**. AssemblyAI offers SOC2 and HIPAA compliance but does not hold ISO 27001 certification. Combined with Speechmatics' on-premises and air-gapped deployment options, this makes Speechmatics the stronger choice for security-conscious enterprises.

### Can I switch from AssemblyAI to Speechmatics easily?

Yes. Speechmatics offers a straightforward REST API and [WebSocket interface](https://docs.speechmatics.com/speech-to-text/realtime/quickstart) for real-time transcription. To help you evaluate the switch, we are offering **$200 in free credits** with the code **SWITCH200**. Our customer success team provides hands-on migration support, and G2 reviewers rate Speechmatics **95% for being a "Good Partner in doing business"** versus AssemblyAI's 90%.

### Does Speechmatics have a specialist medical model?

Yes. Speechmatics includes a dedicated [Medical Model](https://www.speechmatics.com/use-cases/medical-transcription) purpose-built for clinical documentation — trained on SNOMED CT terminology, FDA/MHRA drug names, and real clinical audio. It delivers up to 50% fewer critical errors compared to general models, with 96% medical term recall, available for real-time transcription across English, French, German, Spanish, Danish, and Norwegian. AssemblyAI has no equivalent dedicated medical speech model. See the [Medical Model launch announcement](https://www.speechmatics.com/company/articles-and-news/speechmatics-launches-medical-model-for-real-time-clinical-transcription) and the [Humetrix case study](https://www.speechmatics.com/product/case-studies/humetrix-multilingual-medical-transcription) — where Speechmatics replaced Whisper for multilingual clinical transcription across 27 languages at the Paris 2024 Olympics.

### What is Melia — Speechmatics’ multilingual model?

[Melia](https://www.speechmatics.com/company/articles-and-news/introducing-melia-multilingual-speech-to-text-model) is Speechmatics’ new multilingual speech-to-text model with native code-switching across all 56+ supported languages in a single pass — no per-language model selection needed. It outperforms Deepgram, Microsoft, and AssemblyAI on most FLEURS language benchmarks, making it the strongest option for multilingual content, accented speakers, and global deployments. Priced from $0.129/hr for batch (10 hrs/month free), it’s also the most affordable model in the Speechmatics range. AssemblyAI’s multilingual real-time streaming is limited to a subset of European languages.

## **Ready to switch to superior speech-to-text?**

Join thousands of developers building the future of voice with Speechmatics. 
Get $200 in free credits when you sign up today.

- [Get Started](https://portal.speechmatics.com/signup/)
- [Contact Sales](https://www.speechmatics.com/speak-to-sales)

## Resources for AI Voice Agents

### Voice Agents — Vapi and Speechmatics: Build agents that understand every voice

- [Vapi and Speechmatics build better agents](https://www.speechmatics.com/company/articles-and-news/vapi-and-speechmatics-build-agents-that-understand-every-voice)

Ship Voice AI agents that stay readable in real time, even in noisy, multi-speaker calls.

- Speechmatics — Editorial Team

### Voice Agents — Introducing real-time, speaker-aware Voice Agents with LiveKit + Speechmatics

- [Introducing real-time, speaker-aware Voice Agents with LiveKit + Speechmatics](https://www.speechmatics.com/company/articles-and-news/build-ai-agents-that-understand-who-said-what-livekit)

Speechmatics brings speaker diarization to LiveKit agents - enabling them to understand not just _what_ was said, but _who_ said it.

- Anthony Perera — Product Marketing Manager

### Voice Agents — Pipecat and Speechmatics: Building Voice Agents that know exactly ‘Who’ said ‘What’

- [Pipecat and Speechmatics: Building Voice Agents that know exactly 'Who' said 'What'](https://www.speechmatics.com/company/articles-and-news/pipecat-and-speechmatics-building-voice-agents-that-know-exactly-who-said-what)

Build smarter voice agents on Pipecat with Speechmatics speech-to-text, now with powerful speaker diarization for real-world, multi-speaker conversations.

- Speechmatics — Editorial Team

### AI Agent Builder — How to build a conversational agent in less time than Cupid’s arrow takes to strike

- [Eros blog](https://www.speechmatics.com/company/articles-and-news/how-to-build-a-conversational-agent-in-less-time-than-cupids-arrow-takes-to-strike)

What happens when you set out to build a fully functioning AI love guru with very little turnaround time?  Let's find out...

- Farah Gouda — Data Engineer