ToneSub

ExtensionEducation

Overview

Fast bilingual subtitles for YouTube videos, with automatic target-track and translation fallback.

ToneSub adds fast bilingual subtitles to YouTube videos. It displays the original captions alongside a target-language translation, automatically preferring YouTube’s available target-language caption track and using a translation fallback when needed. Customize subtitle order, position, font, size, colors, background, and outline to match your viewing style. Optional DeepSeek BYOK AI enhancement is off by default. It only activates after you provide your own API key, confirm the in-extension data disclosure, and grant the optional permission. ToneSub works only on YouTube video pages. It has no ads, no account system, and no developer-operated backend.

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Details

Version
1.1.4
Updated
July 22, 2026
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Offered by
mk18560884319
Size
126KiB
Languages
3 languages
Developer
Sun Yuhe
No.60,Dongsun Village,Fangzhen Town 淄博市, 山东省 255000 CN
Email
mk18560884319@gmail.com
Phone
+86 185 6088 4319
Trader
This developer has identified itself as a trader per the definition from the European Union and committed to only offer products or services that comply with EU laws.

Privacy

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ToneSub has disclosed the following information regarding the collection and usage of your data. More detailed information can be found in the developer's privacy policy.

ToneSub handles the following:

Website content

This developer declares that your data is

Not being sold to third parties, outside of the approved use cases
Not being used or transferred for purposes that are unrelated to the item's core functionality
Not being used or transferred to determine creditworthiness or for lending purposes

Support

For help with questions, suggestions, or problems, visit the developer's support site