How to check your browser's privacy with 30 lines of JavaScript — and what I learned

ToolAnchor — Wed, 08 Jul 2026 16:15:00 +0000

What most people don't know about their browser

Your browser leaks more than you think — and you don't need a third-party tool to check it. Most of the signals you need are already in the browser's native APIs.

The 6 checks I run (and the JS code)

1. HTTPS status
window.location.protocol === 'https:'

2. Cookies enabled
navigator.cookieEnabled

3. Local storage available
Try/catch a localStorage.setItem() call

4. Do Not Track signal
navigator.doNotTrack === '1'

5. Private/Incognito heuristic
Check localStorage quota — private mode caps it at ~5MB in most browsers

6. Browser detection
navigator.userAgent parsing for Chrome/Firefox/Safari/Edge

Turning it into a score

Each check that passes adds points to a score out of 100. I weight DNT and HTTPS more heavily because they have the most real-world impact.

What I built with this

A free browser privacy checker that runs these 6 checks instantly and gives you a score, a verdict, and a personalized list of things to fix.

👉 Browser Privacy & Security Checkup

What I want to add next

WebRTC leak detection (navigator.mediaDevices.enumerateDevices)
Canvas fingerprint score
Third-party cookie isolation check

What would you add? Have you built something similar?

I built a WiFi QR Code Generator that runs 100% in your browser

ToolAnchor — Fri, 03 Jul 2026 16:20:00 +0000

The Problem

Sharing your WiFi password out loud is awkward. Typing it on a guest's phone takes forever. And some passwords are 20+ characters.

The WiFi QR Code Trick

A WiFi QR code encodes your network credentials in a format phones understand natively — iOS 11+ and Android 10+ both support it without any app. Guest scans it, connects instantly.

The QR string format looks like this:
WIFI:T:WPA;S:YourNetworkName;P:YourPassword;;

How I Built It (in 40 lines of JavaScript)

[paste 20–30 lines of your actual JS generator code here]

The key is using a QR library like qrcode.js and building the WIFI: string dynamically from the form inputs.

What I Added for Better UX

Show/hide password toggle
Network type dropdown (WPA2, WPA3, WEP, None)
Hidden network checkbox
One-click download as PNG

Real Use Cases

I designed this with 4 scenarios in mind:

House guests who can't connect
Airbnb hosts who change passwords monthly
Office WiFi for visitor access
New home setup — print it and stick it on the router

Try It Free

👉 WiFi QR Code Generator — no signup, nothing stored.

I also built a Password Generator and a Browser Privacy Checker as part of the same toolkit.

DEV Community: ToolAnchor