context-wise.com

What It Is

ContextWise is an AI Chrome extension for YouTube, described by the company as a “YouTube First AI Assistant.” It is mainly designed for English learning: while users watch English YouTube videos, the extension analyzes context based on subtitles, and when they encounter expressions they do not understand, they can use Ask AI to get explanations of background, tone, and cultural nuance. The product is operated by the Japanese company 株式会社サイジ.

Core Features

Its main features include real-time bilingual subtitles, keyboard shortcuts for replaying subtitle segments or jumping backward and forward, AI-powered contextual Q&A, and automatic saving of previous questions and answers. Compared with standard subtitle translation, ContextWise places more emphasis on “why this sentence is phrased this way” and “what it means in this specific context.” However, the page does not disclose the underlying model, whether it uses third-party LLMs, which output languages are supported, or any accuracy data or side-by-side examples.

Pricing and Trial

The product offers a free plan and can be installed from the Chrome Web Store. The paid monthly plan costs税込 $2.0, paid by credit card via Stripe, with automatic monthly renewal. The specific limits of the free tier are not disclosed, such as the number of AI Q&A requests, supported video length, or history storage limits. As a lightweight learning tool, the price is low, but users should still confirm the differences between the free and paid versions before subscribing.

Pros and Cons

Its strengths are a very clear use case and a closed learning loop around English input on YouTube: subtitles, repeat playback, AI explanations, and review history. Installation is also simple. Learning history is saved automatically, and planned CSV and Anki export support could be valuable for building up vocabulary and sentence collections over time. The limitations are mainly around insufficient disclosure: API and integration capabilities are not mentioned, data privacy information is limited to basic operations and payment details, and it is unclear how question content is stored or used. Chinese UI support and Chinese-language explanation capabilities are also not clearly stated.

Who It’s For and Access from China

ContextWise is suitable for individual learners who mainly use YouTube to study English and often struggle with context and idiomatic usage, especially Japanese users. Access from mainland China cannot be determined from the page; because the product depends on YouTube and the Chrome Web Store, actual usability may be affected by the local network environment. Alternatives include Language Reactor, YouTube bilingual subtitle extensions, Glasp, and general-purpose AI browser sidebar tools.