How to use: Enter text or upload a QR code image. The tool generates a QR code at each error correction level (L/M/Q/H) and hides modules just below and above the tolerance limit to test whether the code is still readable. For example, at Level M (recoverable up to 15%), it generates three QR codes hiding 14%, 15%, and 16% so you can check the boundary.
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Upload QR Code Image
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Drag & drop an image / click
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About QR Code Error Correction Limit Testing

QR Code EC Tester is a free online tool that lets you visually check the limits of the error correction feature of QR codes. When embedding a logo into a QR code or creating a design QR code, you can verify in advance how much you can hide while keeping the code readable.

Comparison of Error Correction Levels

Level Recovery Capacity Use Case
LAbout 7%When maximizing data capacity. Use in clean environments.
MAbout 15%Standard use. The most commonly used level for general QR code generation.
QAbout 25%Somewhat harsh environments. Also supports embedding small logos.
HAbout 30%Logo embedding and harsh printing environments. Ideal for design QR codes.

Use Cases

Ideal for designers who want to place a logo-embedded QR code on business cards or posters, quality control staff who want to verify QR code robustness, and engineers or students who want to understand how error correction works. The center block mask simulates logo placement, while the random scatter mask simulates real-world soiling or damage.

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