# WhisperKit (Argmax) Review

> WhisperKit (Argmax) review: On-device Apple Silicon STT (Whisper). Verified pricing, features, and the strongest alternatives in Speech-to-text APIs.

![WhisperKit (Argmax) logo](https://www.versusref.com/logos/whisperkit.png)

On-device Apple Silicon STT (Whisper)

Among the 43 speech-to-text tools we track, WhisperKit (Argmax) has the 12th-widest language coverage - a fit for multilingual and localization projects.

From $1,330/mo · Open source · facts verified Jul 20, 2026

## What we know about WhisperKit (Argmax)

WhisperKit (Argmax) sits in the speech-to-text apis category, where it is on-device Apple Silicon STT (Whisper). We keep this WhisperKit (Argmax) profile grounded in primary sources, each fact dated to when we last confirmed it.

On pricing, WhisperKit (Argmax) starts at $1,330 per month for its entry tier. That is the sticker rate: real production cost usually runs higher once you add a language model, a voice provider, and telephony minutes.

On capabilities, WhisperKit (Argmax) covers language auto-detection, word-level timestamps, custom vocabulary / keyterm boosting, speech translation, and self-host / on-prem option, and does not offer entity detection, sentiment analysis, and summarization endpoint. Each of those is verified against WhisperKit (Argmax)'s own docs or dashboard, not marketing copy.

WhisperKit (Argmax) ranks the 12th-widest language coverage of the 43 speech-to-text tools we track, so where it lands for you depends on which of those matters more.

In total we track 26 verified facts for WhisperKit (Argmax) today, each linking the primary source it came from so you can check our work - and vendor claims we have not measured ourselves are labeled as such on the WhisperKit (Argmax) fact sheet below.

## Fact sheet

### Pricing

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Pricing model | subscription | Jul 20 | [source](https://www.argmaxinc.com/pricing) |
| Cheapest paid plan | $1,330 | Jul 20 | [source](https://www.argmaxinc.com/pricing) |
| Free tier quota | Unlimited - free OSS, on-device | Jul 20 | [source](https://www.argmaxinc.com/pricing) |
| Published volume discounts | Enterprise discounts; annual rate lower | Jul 20 | [source](https://www.argmaxinc.com/pricing) |
| Concurrency on base plan | Unlimited - runs on-device | Jul 20 | [source](https://www.argmaxinc.com/pricing) |
| Extra concurrency cost | None - on-device | Jul 20 | [source](https://www.argmaxinc.com/pricing) |

### Capabilities

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Languages supported | 99 | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Language auto-detection | ✓  Yes | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Speaker diarization | ✗  Not available | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| PII redaction | ✗  Not available | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Word-level timestamps | ✓  Yes | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Custom vocabulary / keyterm boosting | ✓  Yes | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Entity detection | ✗  No | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Sentiment analysis | ✗  No | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Summarization endpoint | ✗  No | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Speech translation | ✓  Yes | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Priced audio-intelligence add-ons | VAD; SpeakerKit diarization, TTSKit TTS | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |

### Compliance & trust

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Self-host / on-prem option | ✓  Yes | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Model weights license | MIT | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |

### Build experience

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Official SDKs | Swift (Swift Package Manager) + CLI; Pro Kotlin | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Websocket streaming API | ✗  No | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |

### Commercial

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Model size (parameters) | tiny 39M / base 74M / small 244M / large-v3 1.5B | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Hardware to self-host | Apple Silicon (M/A-series), Core ML + ANE | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Hosted API available | No - on-device SDK only | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |
| Project maintenance status | Active - v1.0.0 released 2026-05 | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift/releases) |
| GitHub stars | 6,279 | Jul 20 | [source](https://github.com/argmaxinc/argmax-oss-swift) |

Source: https://www.versusref.com/stt/tools/whisperkit/