VoxSub – AI Subtitle Translator & Dubbing par voxsub

VoxSub is an AI subtitle translator and all-in-one subtitle toolkit for HTML5 video players. Translate subtitles, show dual subtitles (bilingual captions), dub videos with AI voice, filter words, rewrite, search, synchronize, download, and upload subtitle files while you watch.

VoxSub works on any HTML5 video player, even on websites that are not officially supported: if the player exposes its subtitles, VoxSub detects them so you can translate or download them. Supported sites include YouTube, Crunchyroll, Vimeo, Dailymotion, and Bilibili.

Floating Toolbar

A small floating toolbar appears on the video player, so you can translate subtitles or start dubbing in one click, without opening the extension. Use the shield icon to open your subtitle filter profiles, or open the full Control Panel whenever you need more options.

How it works

1. Detect: VoxSub automatically finds the subtitles available on the player, such as YouTube subtitles.
2. Translate: translation works automatically with no API key required. For AI translation and rewriting, you can optionally connect Gemini with your own free API key.
3. Upload: if a video has no subtitles, or the site doesn't expose them (such as Netflix), upload your own subtitle file and use the same tools on it.
4. Dub: AI dubbing works on any player, using detected subtitles or a file you uploaded.

Whether you're learning a new language, watching international content, improving subtitle quality, or creating your own subtitle experience, VoxSub gives you complete control over subtitles without interrupting playback.

Key Features

Dual Subtitles (Bilingual Captions)

Display two subtitle tracks at the same time, such as the original subtitles alongside a translated or rewritten version.

Perfect for language learning, bilingual viewing, and subtitle comparison.

AI Subtitle Translation & Rewriting

Translate subtitles into supported languages or rewrite them using your preferred AI service.

Simplify text, adjust writing style, change tone, rewrite subtitles into different dialects, or create your own custom translation instructions.

AI Voice Dubbing (AI Dubbing)

Turn subtitles into spoken audio on any player, using detected subtitles or your own subtitle file.

Two voice options: a free engine that needs no API key, or ElevenLabs for higher-quality voices. ElevenLabs works with your own API key, and its free plan includes a monthly character allowance with no credit card required.

Control the dubbing speed, dubbed voice volume, and original video volume, with advanced voice settings for ElevenLabs.

Subtitle Filter Profiles (Shield)

Click the shield icon to open your subtitle filter. Create custom profiles that automatically:

• Replace words or phrases in the subtitles with your own text.
• Mute the audio when a chosen word is spoken.
• Skip the subtitle segment where a chosen word appears.

A useful word filter and profanity filter for family-friendly viewing, kids, anime, movies, or any personal preference.

Quick Edit: select any word in the subtitles while you watch and choose Mute, Skip, or Replace instantly, with no setup.

Live counters show how many words were replaced, segments skipped, and audio parts muted. Adjust the skip timing to fit your needs.

Build separate profiles for different kinds of content and switch between them in one click. Import and export your profiles as JSON files. All rules are stored locally in your browser.

Subtitle Downloader & Upload

Download detected subtitles from HTML5 video players, regardless of subtitle length.

Upload your own subtitle files to any supported player and use every VoxSub feature, including translation, rewriting, searching, synchronization, filtering, dual subtitles, dubbing, and subtitle customization. This also works on sites like Netflix, where subtitles can't be detected automatically.

Subtitle Search

Search instantly inside detected or uploaded subtitles.

Jump directly to any matching subtitle line or timestamp without manually searching through the video.

Perfect for studying, reviewing conversations, or finding specific scenes in seconds.

Subtitle Synchronization

Fix subtitle delays in seconds, with two options:

• Quick Sync: a simple timing slider to shift subtitles earlier or later.
• Advanced Sync: pick two reference points (Point 1 and Point 2) from the subtitle cue list, which shows the timing of every line, and search inside it to find the right lines fast.

An easy way to fix subtitle timing without manually editing subtitle files.

Subtitle Customization

Customize how subtitles look from the Control Panel: background opacity, font size, bold text, color, and position on screen. You can also hide the subtitles or the video itself when you only want to listen.

Automatic Subtitle Detection

VoxSub automatically detects subtitles on HTML5 video players, including YouTube, Crunchyroll, Vimeo, Dailymotion, and Bilibili.

If subtitles are unavailable, simply upload your own subtitle file and continue using all subtitle tools without limitations.

More Tools in the Control Panel

Video Adjustments: change brightness, contrast, and saturation to make any video look better.

Audio Boost: boost the volume of quiet videos with one simple slider.

Lightweight & Fast

Designed to stay lightweight, responsive, and efficient while watching videos.

Privacy

Subtitle profiles, settings, and rules are stored locally in your browser.

When you translate or dub, subtitle text is sent to the translation or voice service in use, including Gemini or ElevenLabs if you add your own API key. Details are in the Privacy Policy.

AI features run only when you choose to use them.

Why Choose VoxSub?

• Detect and download subtitles on HTML5 video players.
• Translate subtitles automatically, no API key needed.
• Display dual subtitles.
• AI dubbing with a free voice or ElevenLabs.
• Quick access from a floating toolbar on the player.
• Filter profiles: replace words, mute audio, or skip segments, with Quick Edit on any subtitle word.
• Rewrite subtitles using custom AI instructions.
• Upload your own subtitle files, including for Netflix.
• Synchronize subtitles with a quick slider or two-point Advanced Sync.
• Search subtitle text instantly.
• Customize subtitle color, size, position, and background.
• Boost volume and adjust brightness, contrast, and saturation.
• Lightweight, fast, and easy to use.