Laser engraving & cutting DXF
Here the code is measured in millimetres, like the real part. The DXF
comes out on three layers — QR_GRAVURA (engrave), QR_GAURI
(do not engrave), TAIERE (cut) — which the machine treats differently.
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The code is generated in your browser. Nothing you type is sent to a server.
QR code to DXF, for laser engraving and CNC
Most QR code generators give you a PNG. A raster image is the wrong input for a machine that follows contours: you end up tracing it by hand, and the traced outline never quite matches the code. This one exports the DXF directly, in millimetres, from the same geometry that draws the preview — so what you see is what gets cut.
What is in the DXF
Three layers, because a laser treats them differently:
QR_GRAVURA— the closed contours to engrave or mark.QR_GAURI— the areas that must stay unengraved: the holes inside the three finder patterns. Kept separate so you can subtract them instead of guessing.TAIERE— the outline of the part itself, when you choose a shape.
Units are millimetres ($INSUNITS = 4). The file is plain DXF R12, which
LightBurn, RDWorks, LaserGRBL, CorelDRAW, Fusion 360 and Illustrator all open without
conversion.
The number that decides whether it will scan: module size
A QR code is a grid of squares called modules. Everything about engraving comes down to how many millimetres one module gets.
Below roughly 0.30 mm per module, laser engraving on metal stops holding a clean edge — the melted zone spreads into the neighbouring module and the contrast the scanner needs disappears. This tool measures the module size for your part and warns you before you cut, instead of after.
Two ways to buy yourself margin, both free:
- Shorten the data. Encode a short link, not the whole payload. A URL written in CAPITALS uses about 35% fewer bits than the same URL in lower case, because it fits the alphanumeric mode. This generator picks that mode automatically when it can.
- Make the part bigger. Module size scales linearly with the part, so going from 20 mm to 25 mm buys 25% more per module.
For reference, a 21-character URL at error correction H on a 20 mm part:
| Part shape | mm per module | Engravable on metal |
|---|---|---|
| no outline | 0.606 | yes |
| rounded square | 0.549 | yes |
| circle | 0.461 | yes |
| oval | 0.337 | marginal |
| heart | 0.261 | no — needs 23 mm |
Contrast, not depth
The most common failure when engraving a QR code on metal is not resolution — it is that the finished part has no optical contrast. A phone camera does not see relief; it sees light and dark. Polished silver engraved into polished silver is invisible to it, and the specular reflection can saturate the sensor outright.
What works: a blackened (oxidised or filled) engraving on a matte background. Inverting it — engraving the field and leaving the modules polished — is usually worse. Test on scrap before you run a batch.
Use error correction H
An engraved part gets scratched, handled and tarnished. Level H tolerates about 30% of the code being damaged or obscured, and it is what makes a centre logo survivable. The extra modules cost you a little density; the reliability is worth it.
Notes per material
- Stainless steel, titanium — fibre laser marking gives excellent contrast; the easiest case.
- Silver, gold, brass, copper — highly reflective. Engrave and blacken, then bring the surrounding surface to matte.
- Anodised aluminium — ablating the anodised layer gives near-perfect contrast at low power; the best material for small codes.
- Wood, leather, acrylic — forgiving on contrast, but the beam kerf is wide relative to a small module. Go bigger than you think.
Questions
Is it free? Yes. No account, no watermark, no scan limit, no subscription. The codes are static: once downloaded, they work forever and do not depend on this site staying up.
Does my data leave the browser? No. The encoding, the geometry and all three exports are computed locally in JavaScript. Nothing is uploaded.
Can the code follow a round outline? No, and be suspicious of anything that claims otherwise. The standard requires a square grid with straight timing patterns. The part shape here is a frame around the square code, not a deformation of it.
Why is the Y axis flipped compared to the SVG? DXF measures Y upward, SVG downward. The export accounts for it — the code is not mirrored. If you ever get a mirrored engraving from another tool, this is the usual reason.
Can you engrave the parts for me? Yes — we run the laser that this tool was originally written for. Talk to the workshop.