QR Code Generator | Custom QR Codes

The most overlooked setting in any QR generator is error correction. For a sticker, label, or printed card that will get scratched or wet, use H (30% damage recovery). For a URL on a screen or slide, L (7%) is fine — it scans faster and from greater distances. Using H on a screen just adds density for no benefit.

Seven content types cover practical use cases: URL, plain text, Wi-Fi credentials, email, phone, SMS, and vCard contacts. Wi-Fi and vCard are the genuinely useful ones — they eliminate manual data entry entirely rather than just saving a click.

Error Correction Levels — L, M, Q, H and When Each Makes Sense

Reed-Solomon error correction lets a scanner reconstruct data even when part of the code is damaged. Level L allows 7% of modules to be unreadable. M allows 15%. Q allows 25%. H allows 30%. Higher correction requires more modules for the same payload — the code looks busier.

For clean digital displays, L is almost always right. The code is smaller, less dense, and scans faster. For standard printed materials, M provides useful margin. Q is the right default for real-world environments where a code might be near a fold or printed on absorbent paper. H is for physical products: labels, packaging, stickers, anything handled repeatedly.

The common mistake: using L for product packaging because "it looks cleaner." A small scratch on a low-correction label makes it completely unscannable. Use H on physical products.

PNG vs SVG — Which Format to Download

PNG stores pixels at a fixed resolution. A 400×400 PNG is sharp at 400px but blurry at 800px. Use PNG for digital contexts: email, social posts, websites, slides — anything displayed at a predictable screen size.

SVG stores the code as geometric shapes that render at any resolution. One SVG file prints identically at 2 cm or 2 metres. Use SVG for everything printed: business cards, brochures, packaging, banners. Illustrator, Affinity Publisher, Figma, and Canva all import SVG correctly.

Watch for one SVG trap: some applications rasterize imported SVGs at low resolution before printing. If print looks blurry despite using SVG, check your layout software's import settings or send the SVG directly to the print shop.

UTM Parameters and Print Campaign Analytics

UTM parameters classify traffic by source in analytics. Without them, every scan from every printed QR code shows as "direct" — indistinguishable from someone typing the URL. With utm_source=brochure and utm_medium=print, you get a separate traffic segment.

The five standard parameters: utm_source (where the code appears), utm_medium (the channel), utm_campaign (the campaign name), utm_term (keyword tracking), utm_content (differentiates multiple codes in one campaign). Consistent naming matters — "Brochure" and "brochure" appear as separate sources in reports.

Contrast Ratio, Quiet Zone, and Why Codes Fail to Scan

Two physical factors cause most scan failures: insufficient contrast and missing quiet zone. Contrast must be at least 4.5:1 between dark modules and the light background. Below that, codes fail in dim light or with slightly out-of-focus cameras. Dark blue on black, white on yellow, light grey on white — all fail.

The quiet zone is the blank border around the code. The QR spec requires at least 4 modules wide on all four sides. Scanners use this border to locate the finder pattern squares. Crop it in a print layout and scanners either can't find the code or produce intermittent failures. This is the most common print design mistake.