# How I built a Chrome extension that reads Terms of Service using AI — and what I found

> Source: <https://dev.to/francisco_javiernovesmo/how-i-built-a-chrome-extension-that-reads-terms-of-service-using-ai-and-what-i-found-1mi>
> Published: 2026-07-10 16:30:17+00:00

##
The problem that made me build this

Every time I signed up for a new app or service, I clicked "I Agree" without reading a single line. Nobody reads Terms of Service. They're 30+ pages of dense legal language designed to be ignored.

But I kept hearing horror stories:

- Apps training their AI on your private photos
- Subscriptions auto-renewing for €99/year after a free trial
- Platforms stripping your right to sue them (forced arbitration)
- Companies sharing your data with hundreds of "partners"

So I built **ToS Radar PRO** — a Chrome extension that reads the fine print so you don't have to.

##
How it works

The extension uses AI to scan any Terms of Service or Privacy Policy page and flags six categories of dangerous clauses:

-
**AI/Data Scraping** — "We may use your content to train our AI models"
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**Forced Arbitration** — You waive your right to take them to court
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**Auto-Renewals** — Subscription traps buried in paragraph 47
-
**Data Sharing** — Your data sold to advertisers and data brokers
-
**Unilateral Changes** — They can change the terms anytime without notice
-
**Account Termination** — They can delete your account for any reason

The key architectural decision: **everything runs locally in your browser**. No API calls, no external servers, no data leaving your machine. Pure privacy.

##
Tech stack

- Chrome Extension Manifest V3
- Vanilla JavaScript (no frameworks — keeping it lean)
- Local AI inference via the browser
- Zero external dependencies

##
What I found while testing

After running it against 50+ popular websites, here are the most common traps:

-
**97%** of apps reserve the right to train AI on your data
-
**83%** include forced arbitration clauses
-
**76%** have auto-renewal terms that are hard to find
-
**100%** reserve the right to change terms at any time

The worst offenders? Social media platforms and productivity SaaS tools.

##
Try it free

ToS Radar PRO is completely free on the Chrome Web Store:

[Install ToS Radar PRO](https://chromewebstore.google.com/detail/tos-radar-pro-%E2%80%93-ai-legal/ldmpbnpnflpglocpaocojmlffnbglngi)

Would love feedback from the DEV community — especially on the tech approach and features you'd want added. What clauses do you care about most?