FastCheck icon

FastCheck

by ymalovany@gmail.com · Privacy & Security
Manifest V3 in_app
View in Chrome Web Store Data as of 15 Oct 2026

Local AI fact-checker with right‑click auto-verify. No API keys required (WebLLM).

Users
21
−1 in 30 days
Rating
0.0 / 5
unchanged in 30 days
Ratings
0
0 in 30 days
Store rank
#148K
#123K among extensions
Version
5.0.0
updated 17 Sep 2025

Users

monthly, 13 months
01021Sep 2025Apr 2026Oct 2026
Latest, 15 Oct 2026: 21 usersMove the mouse over the chart for any month

Ratings count

monthly, 13 months
001Sep 2025Apr 2026Oct 2026
Latest, 15 Oct 2026: 0 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About FastCheck

📖 FastCheck – Local AI Fact-Checker (Chrome Extension) Verify information instantly with the power of AI — right inside your browser FastCheck is a lightweight, privacy-friendly Chrome extension that helps you verify claims, news, and facts without leaving the page you’re on. Simply highlight any text, right-click, and choose “FastCheck: fact-check” — the extension automatically analyzes the statement using local AI (WebLLM) and shows you whether it’s true, false, or misleading. No API keys, no accounts, no third-party servers. Everything runs locally in your browser, using modern WebGPU acceleration for efficiency. This means your text never leaves your computer — keeping your browsing private and secure. 🌟 Key Features Right-Click Instant Fact-Check Highlight any text → right-click → “FastCheck” → get a fact-check result instantly in the popup. No need to copy/paste manually. Classic, Simple UI A clean and intuitive popup design with an input box, a single Verify button, and clear results. Easy to use even for first-timers. AI-Powered Analysis FastCheck uses a locally running language model to assess statements. It gives you: A verdict (true, false, partially true) Supporting explanation in natural language (When possible) correction of misleading claims Hints about who might benefit from spreading the false/misleading claim Privacy by Design All processing happens locally in your browser with WebLLM. Your selected text is never sent to an external server. No Setup Needed Unlike other AI tools, FastCheck works out of the box. No API keys, no accounts, no hidden costs. Mock Fallback If the local AI model isn’t fully ready, FastCheck still provides heuristic answers so you’re never left hanging. Loading Feedback See exactly what’s happening: “Loading local model…” while AI initializes A progress spinner during analysis “Done” when your result is ready 🔍 Example Use Cases Reading the news: Wonder if a political claim is real or propaganda? Highlight it, right-click, and let FastCheck analyze it. Health and lifestyle content: Encounter a headline like “Burgers are good for your liver”? FastCheck explains why it’s misleading and who benefits (e.g., big food corporations). Academic research: Quickly double-check historical or scientific claims while studying online. Social media browsing: Fact-check viral claims before sharing them. 🛡️ Privacy & Security Runs fully offline in your browser once the model is loaded. No cloud servers, no external requests for your text. Open design using WebLLM for transparent local inference. Only lightweight telemetry (if enabled in your browser) — no user tracking or data selling. ⚡ Performance & Technology FastCheck leverages WebLLM and WebGPU to bring AI inference directly to your device: Powered by TinyLlama (1.1B parameters), optimized for browsers. Automatically loads the best available model supported by your system. Designed to be fast enough for everyday fact-checking while staying lightweight. 🧭 How to Use Install the extension from the Chrome Web Store. Right-click any text you want to verify → choose “FastCheck”. The popup will appear, auto-paste the text, and start analyzing automatically. Or, click the extension icon → paste any text → click Verify. Read the AI-generated verdict and supporting explanation. 📌 Why Choose FastCheck? Unlike traditional fact-checking sites, you don’t need to search manually — the analysis comes to you. Unlike AI chatbots, you don’t need an account, API key, or subscription. Unlike server-based tools, your privacy is guaranteed because everything runs locally. Unlike extensions with vague results, FastCheck shows both a verdict and a rationale. 🚀 Roadmap We are continuously improving FastCheck. Planned features include: Support for switching between multiple local models (e.g., Qwen, Mistral). Better formatting of results (truth percentage, bias breakdown). Optional integration with trusted fact-checking databases for cross-reference. Export and share fact-check reports. 💬 Feedback & Support We want FastCheck to be as helpful as possible. If you encounter bugs, have ideas, or want to contribute: Leave a review in the Chrome Web Store. Share feedback through our support email. Join our open-source community on GitHub. 📝 Disclaimer FastCheck uses AI models to analyze claims. While it strives for accuracy, results are not guaranteed to be 100% correct. Always consider multiple trusted sources when evaluating important information. FastCheck is intended as an assistive tool, not a replacement for professional fact-checking or critical thinking. ✅ FastCheck empowers you to think critically, avoid misinformation, and browse the web with confidence — all with one right-click.

Growth

WindowUsersChangeRatingsRating
7 days0+0.0%00.00
30 days−1−4.5%00.00
6 months+5+31.2%00.00
1 year+21–00.00

Version history

1 versions recorded
5.0.017 Sep 2025

Details

Category
Privacy & Security
First seen
17 Sep 2025
Size
9 KB
Languages
en
Pricing
in_app
Extension ID
fjmjomicckmkmempkbiffhiponanfhbn

Permissions and risk

Moderate riskimpact 2, likelihood 2
Permissions
storagecontextMenusactiveTab
Site access
<all_urls>
Can read and change data on every website you visit.

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