// Stress Test

Test Your QR Code Before You Print It

Stress-test QR codes against camera shake, low light, glare, screen moiré, low contrast, distortion, downscaling, compression, corner damage, and other common real-world conditions — then see exactly what to fix before you commit to print.

14Stress Tests
100%Client-Side
0Images Uploaded
0Account Required

Upload your QR code

Drag & drop, click to browse, or paste an image (Ctrl/Cmd+V)

Supports PNG, JPG, WebP, and SVG.

Your QR image is processed locally in your browser and is not uploaded.

QR Analysis

Uploaded QR code preview
Payload
—
Matrix
—
Image Size
—
Module Size
—
Quiet Zone: Unknown
Error Correction Budget: Level M (15% Recovery)
Camera & Optics
Blur (× module size)
Motion Blur (× module size)
Low Light (intensity)
Glare (intensity)
Screen Moiré (intensity)
Print & Reproduction
Contrast (% of normal)
Compression (JPEG quality)
Print Noise (intensity)
Surface Curvature (% of image height)
Placement & Design
Rotation / Perspective (°)
Central Obstruction (% of symbol area)
Corner / Finder Damage (% of side)

Downscale target sizes (500 / 250 / 150 / 100 px) use fixed steps designed to show the trend as an image shrinks. Real-World Combo is composed automatically from the settings above, so it has no sliders of its own.

Starting…

GOOD

Simulation Score: 0%

This is a simulation covering 14 common real-world conditions across camera/optics, print & reproduction, and placement & design — not a guarantee of how any specific phone, printer, or lighting condition will perform.

Test Results

Recommendations

// How It Works

Upload → Test → Fix

Drag or Browse
01

Upload Your QR Code

14 Stress Tests
02

Run the Stress Suite

Fix & Retest
03

See What to Fix

QuickQRC
Technical Brief · No. 0004
articles/qr-scannability-tester.html
// FAQ

Frequently Asked Questions

No. It simulates common real-world conditions and re-decodes the result with a browser-based decoder. It is a useful early-warning check, not a certification, and it cannot predict every phone, printer, or lighting situation.

No. Decoding, every simulation, the comparison images, and the analysis all run locally in your browser. The image is never uploaded, and the payload stays masked until you press Reveal.

The share of individual decode attempts that succeeded across the run: the baseline decode, the quiet-zone check, and 42 stressed decodes. It is a summary number, not a prediction of real-world scan reliability.

Each one retunes every severity slider at once to match a surface and setting: kraft card, glossy packaging, a distant billboard, or a dim venue. Start from the preset closest to where your code will be scanned, then adjust individual sliders if needed.

The validator gives a fast go/no-go verdict, a PDF report, and a batch mode for up to 100 links. This tester is for one code at a time: you control each condition's severity and see the stressed image beside the original. Use the validator to decide, this to investigate.

The blank margin around a code helps a scanner find where it starts and stops. Too little margin, or a code crowded by other graphics, can make an otherwise-fine code fail. The tool measures it from the code's position in your uploaded image.

Yes. The Central Obstruction test overlays progressively larger patches in the middle of your code and re-decodes after each, so you see the actual failure point for your specific code rather than a generic rule.