QRonimo
QR Code FAQ — QRonimo
QRonimo
QRonimo FAQ

Frequently Asked Questions

Quick answers to the most common QR code questions — from how much data fits to why a code fails to scan.

Data & Capacity

  • It depends on the content type and error correction level. The maximum at level L (lowest redundancy, highest capacity) is:

    Content type Max at level L Max at level H
    Numeric (digits only)7,0893,057
    Alphanumeric (A–Z, 0–9)4,2961,852
    Bytes / UTF-8 (URLs, text)2,9531,273

    In practice, a typical short URL (20–40 characters) fits in a version 1–3 code, the smallest and fastest to scan. Long URLs with tracking parameters can push into version 7–10 territory. The shorter the content, the smaller and more reliable the code.

  • Yes, directly. A longer URL requires more data modules, which forces the encoder to use a higher version (larger grid). Every 4-module increase in grid width and height roughly doubles the visual surface area of the code. A URL shortener — or removing unnecessary query parameters — can reduce a version 8 code down to version 3, making it smaller, denser in appearance, and more reliably scannable in poor conditions.

    There is no benefit to using a long URL in a QR code. The code is not more "trustworthy" with a long URL — and a shorter URL produces a code that is faster to scan and more forgiving of printing imperfections.

    • Scanning & Reliability

  • ProblemFix
    Low contrast (light modules on light background)Aim for at least 4:1 luminance contrast ratio
    Missing quiet zone (blank border)Add at least 4 modules of white space on all sides
    Logo too largeKeep logo under 20–25% of total code area; use error correction level H
    Code printed too smallMinimum 2 cm × 2 cm at 300 DPI; 3 cm with a logo
    Glare from glossy paperUse matte lamination or increase code size
    ECC level L with a logoSwitch to level H — level L cannot recover logo coverage
    Inverted colors (light on dark)Use dark modules on a light background for maximum compatibility

    The fastest diagnostic: try scanning on a different device and in different lighting. If the code scans on a bright screen but not from paper, contrast or print quality is the culprit.

  • Yes. The three finder patterns in three corners of the code allow the scanner to determine orientation automatically. A QR code can be read upside down, rotated 90°, or held at an angle — the decoder corrects for rotation and perspective before parsing the data. This is one of the key design advantages of QR over older 1D barcodes, which require specific alignment.

  • At 300 DPI (standard print resolution): 2 cm × 2 cm minimum without a logo. With an embedded logo, use 3 cm × 3 cm minimum. For codes with dense data (long URLs, vCard data), 3.5 cm without a logo and 4 cm with a logo are safer targets.

    For outdoor signage: the code should be at least 10% of the expected scanning distance. Scanning from 1 m away → 10 cm × 10 cm minimum; from 2 m → 20 cm × 20 cm.

    For screen display: 150 × 150 CSS pixels at standard density (approximately 300 physical pixels on high-DPI displays).

    • Error Correction & Logos

  • Each level specifies how much of the QR code's capacity is devoted to redundant data (error correction codewords) versus the actual content. More redundancy means the code can survive more physical damage — but reduces how much data fits at a given size.

    • L (Low) — ~7% of codewords are error correction. Maximum data capacity. Use for clean printing and screens.
    • M (Medium) — ~15% error correction. The standard default. Good for business cards, brochures, packaging.
    • Q (Quartile) — ~25% error correction. For industrial use, outdoor signage, textured substrates.
    • H (High) — ~30% error correction. Required for logo-embedded QR codes. Also use for extreme-wear environments.

    Full explanation: QR code error correction guide.

  • Yes, and it is a standard technique. The key requirements:

    • Use error correction level H. Level H can recover from up to 30% damage; the logo deliberately covers part of the code and error correction reconstructs what is hidden.
    • Keep the logo under 20–25% of the total code area. 30% is the theoretical maximum; the margin handles real-world wear on top of the logo coverage.
    • Give the logo a solid (non-transparent) background that matches the QR code's light color. A transparent PNG placed on a colored background will confuse the scanner.
    • Never cover the three finder pattern squares in the corners — error correction does not protect these structural elements.

    See the full guide: QR code with logo — design and print best practices.

    • Privacy & Data

  • No. QRonimo generates QR codes entirely in your browser using JavaScript. The text or URL you type into the generator, any logo you upload, and the generated QR code itself never leave your device. There is no server-side processing of QR content and no logging of what you encode.

    The only third-party code on the page is Google AdSense, which operates independently and does not have access to your QR generator inputs.

    Full details: About QRonimo and Privacy Policy.

  • A static QR code (like those generated by QRonimo) is permanent. The encoded data is baked into the module pattern at creation time. If you encode a URL directly, changing the destination requires regenerating the code and reprinting.

    If you want the ability to update the destination after printing, use a URL shortener or redirect service as the intermediary. Encode the short URL in the QR code; then update where the short URL redirects without touching the printed code. Some services (like Bitly or QR-specific platforms) offer this as "dynamic QR codes."

    QRonimo generates static codes only. For most personal and small-business uses — where you control the destination URL — static codes are simpler, do not require a subscription, and never expire.

    • Using QRonimo

  • QRonimo exports QR codes as PNG (raster image, suitable for web and most print workflows) and SVG (vector format, resolution-independent, ideal for large-format print or when you need to edit the file further in Illustrator, Inkscape, or Figma).

    For print: SVG is preferred whenever the destination software can handle it. For web use or email: PNG at 1024 × 1024 pixels or higher is generally sufficient.

  • Yes, completely free. There is no account required, no usage limit, and no watermark on generated codes. QRonimo is funded by Google AdSense advertising displayed on the page.