A pure Swift QR code generator.
QR code generated by SwiftQR
- Pure Swift - Works on macOS and Linux
- All QR versions - Supports versions 1-40 (21x21 to 177x177 modules)
- Multiple encoding modes - Numeric, alphanumeric, and byte
- Error correction - All 4 levels (L, M, Q, H)
- SVG output - Scalable vector graphics with customizable colors and sizing
- PNG output - Cross-platform PNG generation via swift-png
- Built on swift-ascii - Uses PixelGrid for rendering
Add to your Package.swift:
dependencies: [
.package(url: "https://github.com/CorvidLabs/swift-qr", from: "0.1.0")
]import SwiftQR
let qr = try QRCode.encode("https://example.com", errorCorrection: .medium)
// Generate SVG
let svg = qr.svg()
// Generate PNG
let pngBytes = qr.png()let qr = try QRCode.encode("Hello, World!", errorCorrection: .high)
let svg = qr.svg(
moduleSize: 10, // Size of each module in pixels
quietZone: 4, // Quiet zone in modules
foregroundColor: "#000000",
backgroundColor: "#FFFFFF"
)// Low - ~7% recovery, smallest QR code
let qrL = try QRCode.encode(text, errorCorrection: .low)
// Medium - ~15% recovery (default)
let qrM = try QRCode.encode(text, errorCorrection: .medium)
// Quartile - ~25% recovery
let qrQ = try QRCode.encode(text, errorCorrection: .quartile)
// High - ~30% recovery, largest QR code
let qrH = try QRCode.encode(text, errorCorrection: .high)let qr = try QRCode.encode("Test", errorCorrection: .low)
print("Version: \(qr.version.number)") // 1-40
print("Size: \(qr.size)x\(qr.size)") // e.g., 21x21
// Check individual modules
let isDark = qr.module(at: 0, y: 0)
// Get all modules
for (x, y, isDark) in qr.modules() {
// Process each module
}The encoder automatically selects the optimal mode:
| Mode | Characters | Efficiency |
|---|---|---|
| Numeric | 0-9 | 3.3 bits/char |
| Alphanumeric | 0-9, A-Z, space, $%*+-./: | 5.5 bits/char |
| Byte | Any UTF-8 | 8 bits/char |
// Numeric mode (most efficient for numbers)
let qr1 = try QRCode.encode("12345678901234")
// Alphanumeric mode (uppercase only)
let qr2 = try QRCode.encode("HELLO WORLD")
// Byte mode (any text)
let qr3 = try QRCode.encode("Hello, World!")swift run qr-gen > output.svgModify Sources/qr-gen/main.swift to customize the output.
public struct QRCode: Sendable {
public let version: QRVersion
public let errorCorrectionLevel: QRErrorCorrectionLevel
public let size: Int
public static func encode(
_ text: String,
errorCorrection: QRErrorCorrectionLevel = .medium
) throws -> QRCode
public func module(at x: Int, y: Int) -> Bool
public func modules() -> [(x: Int, y: Int, isDark: Bool)]
public func svg(
moduleSize: Int = 10,
quietZone: Int = 4,
foregroundColor: String = "#000000",
backgroundColor: String = "#FFFFFF"
) -> String
public func png(
moduleSize: Int = 10,
quietZone: Int = 4
) -> [UInt8]
}public enum QRErrorCorrectionLevel: String, Sendable, CaseIterable {
case low = "L" // ~7% recovery
case medium = "M" // ~15% recovery
case quartile = "Q" // ~25% recovery
case high = "H" // ~30% recovery
}public struct QRVersion: Sendable {
public let number: Int // 1-40
public var size: Int // 21-177 (17 + 4*version)
}public enum QREncodingMode: Sendable {
case numeric
case alphanumeric
case byte
public static func optimal(for text: String) -> QREncodingMode
}MIT