Lupe – QR code and barcode scanner for the PC

Scan a QR code on your PC – without a phone

QR codes and barcodes often sit exactly where a phone does not help: in a PDF invoice, an e-mail, a web page, a video call or on a delivery note next to the computer. As a QR code reader for PC, Lupe reads them directly and hands the content on to where it is needed – the clipboard, keyboard input into a form, or a link.

Read a QR code from the screen – and barcodes too

Press Win+Shift+Q in any program and drag a rectangle around the code – across all monitors, also with the Lupe window closed. A click without dragging takes the whole monitor, Esc cancels; on the Mac the shortcut is ⌘+⌥+Q. Small codes on big screens are found through an overview plus overlapping tiles in full resolution, and if needed in a thorough second pass. You scan a barcode from the screen the same way, for example the EAN in a web shop or the Code 128 on a delivery note PDF.

Webcam as a barcode scanner

Hold a code in front of the camera: Lupe marks it and beeps. With typing switched on, the webcam works like a hand scanner and types every code into the program in front, such as Excel or an ERP form. The same code is reported again only after it has been out of sight for three seconds.

Codes from images, screenshots or the clipboard

Open an image, drag it onto the File page or press Ctrl+V: Lupe finds every code in the picture and numbers it in reading order. Which image formats work depends on the system: on Windows PNG, JPEG, BMP, GIF, TIFF, ICO and JPEG XR, plus WebP, HEIC, AVIF and JPEG XL with the matching image extension from the Microsoft Store; on Linux PNG, JPEG, BMP, GIF, WebP and ICO; on the Mac PNG, JPEG, GIF, BMP, TIFF, HEIC, WebP and ICO.

Type, copy or open codes as links

• Typing independent of the keyboard layout

  Unicode keyboard input: umlauts, € and emoji arrive as they are – in the window that was active before the scan, optionally followed by Enter or Tab.

• Link rules

  A regular expression and an optional prefix turn a code into a link, e.g. an EAN into the item page of your ERP. Only http and https are ever opened; behind a prefix with a host, the host stays fixed.

• Every code in the picture

  Several codes are reported in reading order. After a screen scan you pick one or copy them all, one per line.

• History with CSV export

  Everything Lupe has read, searchable and exportable as CSV for Excel – stored per user, or switched off, which deletes the file.

• Command line

  Lupe.exe read *.png (or lesen; on Linux lupe read) prints one line per code (format, tab, content) with exit codes 0, 1 and 3 for scripts – without a window and without storing anything.

• Notification area and autostart

  Lupe keeps running in the notification area with its shortcut active; optionally it starts with Windows.

Supported formats: QR Code, Data Matrix and barcodes

22 formats through the zxing-cpp library: QR Code, Micro QR Code, rMQR, Data Matrix, Aztec, PDF417, MicroPDF417, MaxiCode, Code 128 (including GS1-128), Code 39, Code 93, Codabar, ITF (including ITF-14), EAN-13, EAN-8, UPC-A, UPC-E, GS1 DataBar, GS1 DataBar Expanded, GS1 DataBar Limited, Telepen and the DX code on 35 mm film.

Light codes on dark backgrounds – dark mode, displays – are read by the screen scan, from files, the clipboard and the command line; the camera reads light 2D codes.

Switching from commercial desktop QR readers: Lupe as an alternative

If you read QR codes on your PC from the screen or from image files with a commercial desktop QR reader today: Lupe does the same job and offers:

• Screen scan by hotkey (Win+Shift+Q) across all monitors, also with the window closed
• Codes from image files, the clipboard and a webcam – 22 formats, not just QR Code
• Copy the result, type it into the program you came from, or open it as a link through a link rule
• Windows 10 and 11, Linux and macOS; offline, no telemetry, no licence key, free of charge under the MIT licence

Lupe reads codes but does not create them – there is no QR code generator built in.

System requirements

Windows

Windows 10 version 1809 or later, or Windows 11, x64 – MSI, single Lupe.exe or ZIP

Linux

x64 and arm64, X11 and Wayland, glibc 2.31 or later (Ubuntu 20.04, Debian 11 and newer) – .deb (x64) for Debian and Ubuntu, tar.gz for x64 and arm64

macOS

macOS 12 or later, Apple Silicon and Intel – Lupe.app (not yet notarised)

.NET

included in every package except the framework ZIP

Camera

optional; on Windows any webcam that Windows offers to apps

Language

English and German; Spanish, French and Chinese (simplified) machine-translated, not yet reviewed – follows the system language, can be switched

Limits, honestly

• Pre-release 0.1.1, not code-signed and not notarised on macOS: SmartScreen and Gatekeeper warn on first start.
• The camera path is tested against a simulated frame source only, not with a real webcam.
• Linux and macOS are new and less tested than Windows; on a real Mac, Lupe has so far only been started (window, demo camera, command line) – the screen scan, typing, the shortcut and a real camera are untested there. On Wayland, the screen scan, typing and the shortcut go through the desktop portals, which not every desktop offers.
• Lupe cannot type into a program that runs as administrator – it detects this and says so.
• Control characters are not typed, e.g. the group separator in GS1 codes. EAN/UPC add-ons are not part of the result; Intelligent Mail, MSI, Pharmacode and Plessey are not supported.