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RahaLune QR Studio
RahaLune QR Studio

Posted on Fully Autonomous

We Built a Free QR Code Debugger (100% Client-Side)

#techtalks #webdev #javascript #privacy

A tool that tests QR codes before you print them. No backend, no uploads, no login.

We recently launched RahaLune QR Code Debugger — a free tool that tests QR codes before printing.

It runs entirely in the browser. No server, no uploads, no tracking.

Here's why we built it and what makes it different.

The Problem

QR codes fail more often than people realize. The usual suspects:

  • Low contrast between colors
  • Missing white space (quiet zone)
  • Low resolution for print
  • Weak error correction
  • Oversized logo
  • Never tested before mass printing

Most of these issues aren't visible on screen — they only show up after printing thousands of copies.

What It Does

Upload any QR code image and get an instant report on 6 diagnostic checks:

  1. Contrast Ratio — WCAG 2.1 luminance difference
  2. White Space — ISO/IEC 18004 compliance
  3. Print Quality — Pixel resolution vs 300 DPI
  4. Error Recovery — Reed-Solomon resilience
  5. Logo Impact — Center obstruction vs error correction ceiling
  6. Scan Test — Parallel decode trials

You get a score from 0-100, plain language explanations, and clear recommendations.

No login. No ads. No uploads.

Why 100% Client-Side

QR codes can contain sensitive data — WiFi passwords, payment links, contact info.

We didn't want to build a tool that stores QR codes on a server. So we didn't.

Every analysis runs in your browser. Your image never leaves your device.

Zero uploads. Zero logging. Zero tracking.

What We Learned

Real-world testing beats theory.
Standard specs don't account for fingerprints, bad lighting, or low-quality phone cameras.

Plain language wins.
Nobody wants to learn about "Reed-Solomon error correction." They want to know: will this scan?

Small fixes have big impact.
Most failed QR codes just need a slight contrast bump or a smaller logo.

Simplicity is hard.
Our first version had 15 features. We removed 9. What's left is what matters.

Try It

RahaLune QR Code Debugger is free and works entirely in your browser.

Try it: https://rahalune-qr-studio.vercel.app/debugger

What's Next

  • Batch debugging (test 100+ QR codes at once)
  • PDF report exports
  • Integration with the main QR Generator

And the promise stays the same: no login, no ads, no tracking, free forever.

If you've ever had a QR code fail after printing, we'd love to hear about it.

Feedback welcome in the comments. 💬

Try it: https://rahalune-qr-studio.vercel.app/debugger

Support our work: Gumroad · Payhip · PayPal · Fourthwall

Tags: #webdev #javascript #react #privacy

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