asub review
An open-source desktop tool for batch transcription and subtitle translation.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
For technical users who want to generate subtitles locally, asub is an open-source command-line tool for transcribing audio and video. It uses faster-whisper, detects the source language automatically or lets users select it manually, and processes individual files or folders. Its desktop and self-hosted approach suits solo users and small workflows comfortable with Python or command-line tools; it is less suited to buyers seeking a visual editor for caption styling.
Batch processing and translation are central strengths. asub can translate subtitles to 100+ languages through Google Translate, and optional WhisperX-based diarization adds anonymous speaker labels. Voice Activity Detection filtering is also available. Output formats are SRT and WebVTT, so the workflow produces subtitle files rather than documented rendered captions. CPU and GPU execution, quantization options, and Windows executable packaging provide different ways to run the tool; it is available for Windows, macOS, and Linux. Hugging Face is also listed among its integrations.
There are no paid tiers described: asub is open source and has a free plan. The project is marked Beta, and its documentation does not describe maximum video duration, visual caption styling, burn-in rendering, or brand caption presets. That makes it a reasonable fit for technically capable users who need local batch transcription, translation, and subtitle exports, but a weaker choice for teams that want polished on-video captions or a guided interface. Buyers who need those editing capabilities should look for a tool that explicitly provides them.
asub pros and cons
- Where it wins
- Batch-process folders and export SRT or WebVTT subtitles.
- Translate subtitles to 100+ languages and optionally label speakers.
- Run locally on CPU or GPU across Windows, macOS and Linux.
- Where it doesn't
- Command-line workflows require comfort with Python or terminal tools.
- The project is marked Beta.
- Visual caption styling and burned-in video output are not documented.
asub fact sheet, pricing and score →
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