SmartSub

SmartSub: Video subtitle software that generates, translates, dumbs, and burns subtitles locally.

SmartSub is an open source video subtitle desktop application that combines speech to text, subtitle translation, proofreading, AI dubbing, and video synthesis into one workflow. It processes files locally on your device to keep data private while supporting batch tasks and GPU acceleration. The software includes modules for multi engine local transcription, AI enhanced translation with glossaries, video synchronized proofreading, voice cloning and text to speech, video synthesis with hardware accelerated encoding, and online video downloading. It runs on Windows, macOS, and Linux, and offers free local usage with optional cloud services.

SmartSub at a glance

Best for: Social media creator
Runs on: Windows, macOS, Linux
Pricing: Free and open source with local usage limits; optional cloud services
Released: May 2024
Category: AI video tool
Website: smartsub.linxiaodong.com

Key features

Local speech to text transcription with whisper.cpp, faster-whisper, FunASR, Qwen3-ASR, and FireRedASR
Subtitle translation with free sources, DeepSeek, Gemini, and Ollama
Video synchronized subtitle proofreading with search, replace, and AI error correction
AI dubbing and voice cloning with Kokoro, VITS, Edge TTS, ZipVoice, and ElevenLabs
Hard subtitle burning and soft subtitle encapsulation using ffmpeg
Online video downloading from over 1800 sites using yt-dlp and lux
Batch processing with NVIDIA, AMD, Intel, and Apple chip GPU acceleration

Use it for

Generate accurate time-coded subtitles for videos locally
Translate subtitles into multiple languages with custom glossaries
Proofread and edit subtitles with video synchronization
Clone voices and generate AI dubbing tracks for translated videos
Download online videos and automatically create or pair subtitles

Alternatives to SmartSub

AutoSubs — Runs entirely on your machine for free with zero data uploads.
VideoLingo — Automates subtitle cutting, translation, alignment, and dubbing in one click.
pyVideoTrans — Completely open source, free to use, and runs locally with no hardware requirements.
Submagic — Edit shorts 10x faster with AI and automated captioning.
DubbyLab: AI Video Dubbing — Combines transcription, translation, voice cloning and timeline alignment in one pipeline.
ViralWiz — Accurate AI subtitles
YouDub — Runs locally to handle complete video translation and voice cloning pipelines.
Native Subtitle Quote Image — Extracts native embedded subtitles or generates script-based quote images with precise frame capture.
Ssemble — Auto-clips, captions, and posts videos in one click.
Veed — Fast browser editing with top-quality subtitles and dubbing
Publishub — It pinpoints the exact second viewers leave your video and explains why.
AI Video Generator for Brands — Generates videos quickly without filming, actors, or a crew.

All SmartSub alternatives