gchq/CyberChef · error · OperationError

Unsupported QR code format.

Error message

Unsupported QR code format.

What it means

Thrown by generateQrCode when the requested `format` (upper-cased) is not in ['SVG','EPS','PDF','PNG']. This is the entry-point validation before qr-image is invoked.

Source

Thrown at src/core/lib/QRCode.mjs:83

 * Generates a QR code from the input string
 *
 * @param {string} input
 * @param {string} format
 * @param {number} moduleSize
 * @param {number} margin
 * @param {string} errorCorrection
 * @returns {ArrayBuffer}
 */
export function generateQrCode(
    input,
    format,
    moduleSize,
    margin,
    errorCorrection,
) {
    const formats = ["SVG", "EPS", "PDF", "PNG"];
    if (!formats.includes(format.toUpperCase())) {
        throw new OperationError("Unsupported QR code format.");
    }

    let qrImage;
    try {
        qrImage = qr.imageSync(input, {
            type: format,
            size: moduleSize,
            margin: margin,
            // eslint-disable-next-line camelcase
            ec_level: errorCorrection.charAt(0).toUpperCase(),
        });
    } catch (err) {
        throw new OperationError(`Error generating QR code. (${err})`);
    }

    if (!qrImage) {
        throw new OperationError("Error generating QR code.");
    }

View on GitHub (pinned to 4290ea7539)

Solutions

1. Use one of: 'SVG', 'EPS', 'PDF', or 'PNG' (case-insensitive — the check upper-cases).
2. Default the format argument when it may be undefined: `format || 'PNG'`.

Example fix

// before
generateQrCode(text, 'JPEG', 4, 4, 'M');
// after
generateQrCode(text, 'PNG', 4, 4, 'M');

const QR_FORMATS = new Set(['SVG','EPS','PDF','PNG']);
const fmt = String(format ?? '').toUpperCase();
if (!QR_FORMATS.has(fmt)) throw new Error(`Unsupported QR format '${format}'`);
generateQrCode(input, fmt, moduleSize, margin, errorCorrection);

function isQrFormat(f) {
  return ['SVG','EPS','PDF','PNG'].includes(String(f).toUpperCase());
}

try {
  return generateQrCode(input, format, moduleSize, margin, errorCorrection);
} catch (e) {
  if (e instanceof OperationError && /Unsupported QR code format/.test(e.message)) {
    // default to PNG and retry
  }
  throw e;
}

When it happens

Trigger: Calling generateQrCode with a format like 'JPEG', 'GIF', 'BMP', '' (empty uppercases to ''), or undefined (String(undefined).toUpperCase() = 'UNDEFINED').

Common situations: UI dropdown value changed or unset; passing a MIME type instead of the short code; typo in format name; stale recipe referencing a removed format.

Related errors

• Error opening image. (${err})
• Could not read a QR code from the image.
• Error generating QR code. (${err})
• Error generating QR code.
• Unknown padding type: ${padding}

AI-assisted analysis of gchq/CyberChef@4290ea7539 (2026-08-13). Data as JSON: /api/errors/22b398e4de063bc7. Report an issue: GitHub.