# AssemblyAI vs Kaldi

**Leader by Vioscale score:** AssemblyAI

| Attribute | AssemblyAI | Kaldi |
|---|---|---|
| **Vioscale score** | 76.2 (60% (medium)) | 39.6 (15% (low)) |
| activity.commits_last_30d | - | 0 |
| adoption.dependent_repos | - | 1 |
| adoption.github_stars | - | 15,469 |
| deployment.options | `{"cloud":true}` | `{"cloud":true,"self_hosted":true}` |
| description.long | A platform providing speech-to-text APIs for both pre-recorded and live audio, voice agent capabilities, and audio analysis features like speaker identification and sentiment analysis. Serves millions of developers with focus on accuracy and scalability. | A free, open-source framework for building and deploying speech recognition systems, supporting multiple platforms from desktop to mobile and in-browser execution. |
| integrations.count | 5 | - |
| integrations.list | `[{"name":"Semantic Kernel .NET"},{"name":"Vercel AI SDK"},{"name":"OpenAI GPT-5.6 Luna"},{"name":"OpenAI GPT-5.6 Terra"},{"name":"Google Gemini"}]` | - |
| language.primary | - | Shell |
| market.availability | `{"primaryMarkets":["US","GB"],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | - |
| platform.support | `{"web":true}` | `{"cli":true,"mac":true,"web":true,"linux":true,"android":true,"windows":true}` |
| pricing | `{"type":"usage","plans":[{"free":false,"name":"Async Speech-to-Text","summary":"$0.37/hour","components":[{"per":{"qty":1,"unit":"hour"},"kind":"metered","amount":0.37,"currency":"USD"}],"description":"Pre-recorded audio transcription","contactSales":false},{"free":false,"name":"Real-time Speech-to-Text","summary":"$0.47/hour","components":[{"per":{"qty":1,"unit":"hour"},"kind":"metered","amount":0.47,"currency":"USD"}],"description":"Live audio stream transcription","contactSales":false},{"free":false,"name":"Sync Speech-to-Text","summary":"$0.45/hour","components":[{"per":{"qty":1,"unit":"hour"},"kind":"metered","amount":0.45,"currency":"USD"}],"description":"Same-request transcription for short clips","contactSales":false}],"addOns":[{"name":"Speaker Diarization","components":[{"per":{"qty":1,"unit":"hour"},"kind":"metered","amount":0.12,"currency":"USD"}]},{"name":"LLM Prompting","components":[{"per":{"qty":1,"unit":"hour"},"kind":"metered","amount":0.05,"currency":"USD"}]},{"name":"Voice Isolation","components":[{"per":{"qty":1,"unit":"hour"},"kind":"metered","amount":0.1,"currency":"USD"}]},{"name":"SSO","components":[{"kind":"fixed","amount":199,"period":"month","currency":"USD"}]}],"summary":"From $0.37/hour for async transcription. Free tier available.","currency":"USD","freeTier":true,"sourceUrl":"https://www.assemblyai.com/blog/lower-latency-new-pricing","retrievedAt":"2026-08-19T21:32:28.755Z","startingPrice":{"unit":"hour","amount":0.37,"currency":"USD"},"billingPeriods":["month"]}` | `{"type":"open_source","freeTier":true,"sourceUrl":"https://kaldi-asr.org/","retrievedAt":"2026-08-20T12:17:47.249Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | freemium | open_source |
| pricing.price_level | low | free |
| pricing.starting_price | `{"amount":0.37,"currency":"USD"}` | - |
| pricing.transparent | yes | - |
| reliability.sla_pct | 99.9 | - |
| reliability.status_page | yes | - |
| security.disclosure_policy | yes | - |
| security.gdpr | yes | - |
| security.hipaa | yes | - |
| security.pci | yes | - |
| security.scorecard | - | 3.9 |
| security.soc2 | yes | - |
| security.vulnerabilities | - | `{"count":0,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=conda&package_name=kaldi&per_page=100","last_12m":0,"max_severity":null}` |

## Capabilities (Speech To Text)

| Capability | AssemblyAI | Kaldi |
|---|:--:|:--:|
| **Capabilities** |  |  |
| Real time streaming | - | - |
| Speaker diarization | - | - |
| Custom vocabulary | - | - |
| Fine tuning | - | - |
| Word timestamps | - | - |
| Punctuation formatting | - | - |
| Pii redaction | - | - |
| Vertical model | - | - |
| Offline on device | - | - |
| Open source | - | - |

*Source: Vioscale. Generated 2026-09-01T17:40:06.691Z. "-" = undocumented, not absent.*