Dualsub - YouTube Subtitle Translator
By: Dualsub Studio
Translate and display dual subtitles on YouTube and other video websites.
English
Español
Français
Português
日本語
简体中文
한국인
Features & Capabilities
User Growth & Download Statistics
- By:
- Dualsub Studio
- Daily users:
- 4,877 2
- Rating:
- 4.29 (118)
- Version:
- 2.70.0 Last updated: 2026-05-03
- Version code:
- 6245614
- Creation date:
- 2018-10-03
- Risk:
- Moderate risk impact Moderate risk likelihood
- Permissions:
- Host permissions:
- https://www.youtube.com/*
- https://m.youtube.com/*
- https://www.iflix.com/*
- https://www.iq.com/*
- https://www.viki.com/*
- https://www.youku.tv/*
- https://www.zdf.de/*
- https://wetv.vip/*
- https://*.dualsub.xyz/*
- https://www.youtube.com/*
- Content scripts matches:
- www.youtube.com
- m.youtube.com
- www.iflix.com
- www.iq.com
- www.viki.com
- www.youku.tv
- www.zdf.de
- wetv.vip
- www.youtube.com
- Size:
- 32.39KB
- URLs:
- Website
- Full description:
- See detailed description
- Source:
- Firefox Add-ons Store
- Data ingested on:
- 2026-06-17
- Compare stats and ranking:
- Dualsub - YouTube Subtitle Translator vs Dual Subtitles & AI Translation - InterSub
- Dualsub - YouTube Subtitle Translator vs Multi Subsitles Youtube
- Dualsub - YouTube Subtitle Translator vs YouSub
Ranking
Other platforms
For Developers
Contact the developer
Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Permission Change History
2025-11-12: Version 2.66.1 → 2.67.0
Remove Host permissions: https://www.ardmediathek.de/*
2025-11-06: Version 2.65.3 → 2.66.0
Remove Host permissions: https://www.bilibili.com/* https://www.coursera.org/* https://www.udemy.com/*
2025-10-04: Version 2.62.3 → 2.63.0
Add Host permissions: https://www.youtube.com/* https://m.youtube.com/* https://www.ardmediathek.de/* https://www.bilibili.com/* https://www.coursera.org/* https://www.iflix.com/* https://www.iq.com/* https://www.udemy.com/* https://www.viki.com/* https://www.youku.tv/* https://www.zdf.de/* https://wetv.vip/* https://*.dualsub.xyz/*
2025-05-19: Version 2.59.7 → 2.60.0
Remove Host permissions: https://api.dualsub.xyz/*
2024-01-05: Version 1.86.11 → 2.20.0
Add Host permissions: https://api.dualsub.xyz/*
Remove Permissions: https://api.dualsub.xyz/*
User Reviews
Dualsub provides dual subtitles with translation that helps language learning and works on YouTube and other sites. It offers selectable subtitle text and remembers language settings between videos. However, users repeatedly encounter limited language support, site compatibility issues, unadjustable subtitle size, translation quotas, and occasional UX regressions after updates. Pros
- Dual subtitles with translation, helping language learning.
- Works on YouTube (including mobile) and on other sites like Coursera.
- Remembers language settings between videos.
- Translates non-English subtitles into the user's native language.
- Subtitle text can be selected for easier reading or copying.
Cons
- Limited language support; translations are often limited to a few languages and some languages (e.g., Turkish) are not supported; Mandarin translation or languages may show 'unsupported source language'.
- Site compatibility issues; some videos or sites are not supported, and YouTube may report 'website not supported' in some cases (OK.ru also requested).
- Secondary subtitles are large and cannot be adjusted in size.
- Translation service quotas or guest user limits can block translations.
- UX regressions after updates, such as features like style switching or visibility toggles disappearing.
Recent reviews
Was the best Dual Subs App, now does not even translate Mandarin, always "Unsupported source language"
by A *****, 2026-02-22
Perfect for learning a language where the video has both subtitles. Make sure to go into settings and make the text selectable for even more convenience.
by To*****, 2026-02-01
Peut-être que je n'ai pas tout compris mais pour moi il n'y a le choix qu'entre chinois et anglais comme langues traduites, et encore, il faut que la video youtube aie déjà prévu des sous-titres ! Aucun intérêt, donc, j'ai désinstallé...
by Do*****, 2025-11-11
Is Dualsub - YouTube Subtitle Translator Safe?
Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.
Dualsub - YouTube Subtitle Translator requires a few sensitive permissions. Exercise caution before installing.
Risk impact analysis details
- Critical Request access to the following domains: youtube.com, iflix.com, iq.com, viki.com, youku.tv, zdf.de, wetv.vip, dualsub.xyz
- High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.
Dualsub - YouTube Subtitle Translator is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.
Risk likelihood analysis details
- High This extension has low user count. Unpopular extensions may not be stable or safe.
- Medium **** ********* *** ******* ** *** **** * ******* *** ******* *** *** ** ****** ** *****
- Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
- Good **** ********* *** **** **** *******
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