AssemblyAI vs Speechmatics
AssemblyAI
assemblyai.com
Speechmatics
speechmatics.comSide by side
| Figure | AssemblyAI | Speechmatics |
|---|---|---|
| Price from | $0.15/mo | $0.01/mo |
| Free plan | Yes | Yes |
| Free trial | — | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | — | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 13 | 12 |
| Spec score · Podcast Transcription Software | 8.8 (#5) | 8.8 (#7) |
| Spec score · Speech Recognition Software | 8.8 (#8) | 8.9 (#7) |
| Spec score · Audio Transcription Software | 8.8 (#10) | 8.8 (#15) |
| Spec score · Speech-to-Text Software | 8.8 (#10) | 8.9 (#9) |
| Spec score · Transcription tools | 8.8 (#11) | 9.2 (#2) |
| Deployment | Customers can run AssemblyAI in its managed cloud or self-host the models inside their own environment. | The pricing page lists SaaS, multi-region cloud, on-premises containers and virtual appliances, on-device, and hybrid cloud plus on-premises deployment options, with availability varying by plan. |
| Integrations | Official integrations include LiveKit, Pipecat, OpenRouter, Zapier, Make, n8n, Postman, Recall.ai, Zoom RTMS, Telnyx, Twilio, Amazon Connect, Genesys Cloud, LangChain, Vercel AI SDK, Power Automate, Semantic Kernel, Cloudflare, Bubble, Pipedream, and Drupal. | Official integration documentation lists LiveKit, Pipecat, Vapi and Zapier. |
| Security | AssemblyAI offers TLS 1.2+ encryption in transit, AES-256 encryption at rest, zero data retention, and an opt-out from model training. | Speechmatics states it is ISO/IEC 27001:2022 accredited, GDPR compliant, HIPAA compliant and SOC 2 Type II certified. |
| What it does | AssemblyAI provides Voice AI models and APIs for speech-to-text, speech understanding, and voice applications. | Speechmatics provides APIs for real-time and batch speech-to-text, text-to-speech and voice-agent applications. |
Plans
AssemblyAI
- Free creditsFree
- Pay as you go — Universal-2$0.15 a month
- Pay as you go — Universal-3.5 Pro$0.21 a month
- Pay as you go — Universal-Streaming$0.15 a month
- Pay as you go — Universal-3.5 Pro Realtime$0.45 a month
- Free tierFree
- Universal-2$0.15 a month
- Universal-Streaming$0.15 a month
- Universal-Streaming Multilingual$0.15 a month
- Universal-3.5 Pro$0.21 a month
Speechmatics
- FreeFree
- Text to Speech$0.01 a month
- Text to Speech$0.01, paid once
- Melia 1$0.12, paid once
- Melia 1$0.12 a month
- Oak 1 Medical$0.15, paid once
- Oak 1 Medical$0.15 a month
- Standard$0.23 a month
- Standard$0.23, paid once
- Enhanced$0.38 a month
In their own words
AssemblyAI
AssemblyAI provides Voice AI models and APIs for speech-to-text, speech understanding, and voice applications. Its Speech Understanding API can identify and diarize speakers, summarize speech, extract action items and key phrases, detect sentiment, entities, and topics, and handle formatting, language detection, translation, PII redaction, and content moderation. The platform lists support for 99 languages and translation into 86. It offers streaming and voice-agent latency below 300ms and states that it processes more than 800 million API calls per month. Use its managed cloud or self-host models in your own environment; the service also lists API access and integrations including Twilio, Zoom RTMS, Zapier, and LangChain. Security options include TLS 1.2+ in transit, AES-256 at rest, zero data retention, and opting out of model training. A free tier is available. Pay-as-you-go billing is based on usage, with monthly invoices and no minimum commitments. Universal-2 is listed at $0.15 per hour of audio; Universal-3.6 Pro Realtime is $0.45 per hour.
Speechmatics
Speechmatics provides APIs for speech-to-text, voice agents, and text-to-speech, processing recorded files or live audio. Speech-to-text supports more than 55 languages, including conversations that switch languages mid-sentence. The company says real-time transcription can return results in less than one second; speaker diarization and custom vocabulary support speaker identification and specialized terms. Listed uses include healthcare, voice agents, live captioning, contact center analytics, legal transcription, and meeting platforms. Deployment options include SaaS, multi-region cloud, on-premises containers and virtual appliances, on-device, and hybrid cloud with on-premises; availability varies by plan. The service is available through API and on Linux, macOS, Windows, web, and self-hosted platforms. The free plan provides $100 in credits, requires no credit card, and allows two concurrent real-time sessions. Usage-based options include text-to-speech at $0.01 per once and transcription plans priced per hour. Speechmatics states it is ISO/IEC 27001:2022 accredited, GDPR compliant, HIPAA compliant, and SOC 2 Type II certified. It says data is encrypted at rest with AES 256 and in transit using TLS 1.2 or higher.