Privacy Policy — Lex: Learn English with YouTube

Last updated: August 7, 2026

Lex is a Chrome extension that helps people learn English through YouTube videos. This page explains what data Lex collects and how it is used.

What we collect

• Account data: your email address, used to create and sign in to your Lex account. Passwords are stored by our authentication provider in hashed form.
• Learning content: words you click in subtitles, your messages to the AI tutor, and audio you record when using dictation or voice conversation.
• Video subtitles: the subtitle text of YouTube videos you open Lex on. When a video has no subtitles, its audio track may be transcribed instead.
• The page you are on: when you open the Lex chat, the title and address of that page are attached to your message, so the tutor knows what you are asking about. The attachment is shown above the message box and can be removed with the × button before you send.
• Images you attach: if you attach an image to a message, that image is sent with it.
• Usage records: each request to the AI models is logged with its type, time, and cost, linked to your account, so that usage can be displayed and billed.
• Settings: your preferences (models, prompts, display options), linked to your account.

How we use data

Your requests (text, images, and audio) are sent through our server to third-party AI providers — OpenAI, Anthropic, Google, Groq, and Deepgram — to generate word explanations, tutor replies, voice responses, and transcriptions. We use usage records for metering and billing, and technical logs for diagnosing problems.

What we do not do

• We do not sell your data.
• We do not show ads or use your data for advertising.
• We do not track your browsing. Lex sees only the page you have open at the moment you use it — it does not run in the background and does not read your browsing history.

Payments

Payments are handled on our website by a third-party payment processor. Lex does not receive or store your card details.

Storage

Your data is stored with our backend provider (Supabase). Voice recordings and request logs are kept to operate the service.

Deletion

You can request deletion of your account and all associated data by writing to nikolaev.gd@gmail.com.

Contact

Questions about this policy: nikolaev.gd@gmail.com