+Sub

Name: +Sub
Rating: 4.1765 (17 reviews)
Author: stefan.breitenstein

Load subtitle to a HTML5 video.

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+Sub is a powerful Chrome extension designed to enhance your video-watching experience by allowing you to load subtitles on any HTML5 video easily. Whether watching on Netflix, Amazon Video, YouTube, or embedded players in blogs, you can quickly add subtitles with just a few clicks.

The extension features a built-in subtitle search powered by TMDB and OpenSubtitles, enabling you to find your preferred subtitles in multiple languages. Alternatively, you can upload subtitle files from your local machine in popular formats such as *.srt, *.vtt, *.ass, and *.ssa. +Sub also offers synchronization capabilities, letting you adjust subtitle timing directly through an intuitive offset interface.

Beyond displaying subtitles, +Sub can show transcript text that is copyable and interactive—clicking on transcript segments jumps to corresponding video timestamps. For developers and power users, +Sub supports videos within iframes and provides open source access through its GitHub repository. Join the community on Slack for support and discussion.

Add-on

By:

Daily users:

Rating:

Version:

6.5.6 Last updated: 2024-01-16

Version code:

5678262

Creation date:

2018-11-15

Risk:

Permissions:

activeTab
storage
https://*.plus-sub.com/*
https://gqlos.plus-sub.com/*
https://*.opensubtitles.org/**/*
https://*.opensubtitles.com/**/*
webRequest

Size:

759.63KB

Email:

st*****@gmail.com

URLs:

Full description:

Source:

Firefox Browser Add-ons

Data ingested on:

2025-07-10

Ranking

# 4,248 ▼ 20

Other rankings

#85 in loading keyword 24 ▼ 4 #185 in iframe keyword 11 ▼ 1

Other platforms

+Sub (v6.5.2)

10,000 3.79

(123)

User reviews

Pros

Works well on platforms like Paramount Plus and provides good subtitle timing and management.
Small set of permissions required, which enhances user privacy and security.
Valuable tool for expats needing subtitles in various languages.

Cons

Struggles to function properly on Netflix, with subtitles not displaying correctly in full-screen mode.
Frequent loading issues where the add-on does not start or show subtitles, leading to frustration.
Inconsistent performance across different platforms, particularly with Dailymotion and others.

Recent reviews

by 敬念*****, 2025-03-29

by 远离*****, 2025-02-19

It has always worked flawlessly, but recently it doesn't load, the waiting circle keeps spinning and nothing happens :( And it was the best plugin of this type.

by Fi*****, 2024-12-10

View all user reviews ›

Extension safety

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.

+Sub requires a few sensitive permissions. Exercise caution before installing.

Risk impact analysis details

High Allows the extension to observe and analyze traffic in flight for the selected hosts.
Low ******* ****** ** *** ********* ******** ********************

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 Browser Add-ons, 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.

+Sub has earned a fairly good reputation and likely can be trusted.

Risk likelihood analysis details

High This extension has low user count. Unpopular extensions may not be stable or safe.
Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
Good **** ********* *** **** **** *******

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