Kerfview

LightBurn file viewer · nothing uploaded

The difference between .lbrn and .lbrn2.

Both are LightBurn projects, and both open here. .lbrn2 is the current default; .lbrn is the older, larger, more readable format.

or drop a .lbrn2 or .lbrn anywhere on the page

Sample project

hive-coasters.lbrn2

Job sheet

The short answer

LightBurn's documentation says its Save commands offer .lbrn2, the default, or .lbrn, labelled "LightBurn Legacy Project". It recommends keeping .lbrn2 unless you need to work with extremely old versions of LightBurn or want a file that's easy for a person to read. Both hold the same kind of project: layers, cut settings, shapes, images and notes.

What differs inside

Both are XML text. Open either in a text editor and you'll see a <LightBurnProject> element at the top. The root element records the format version: 0 for .lbrn and 1 for .lbrn2. Three differences stand out in real files:

  • Path points. .lbrn2 packs a path's points into one compact string, like V12.5 30c0x1c1x1, and its segments into another, like L0 1B1 2. The older format spells each point out as its own XML element.
  • Settings. .lbrn2 leaves out any setting that equals the default, so a layer might list only speed and power. The older format writes every setting, which makes it long but self-explanatory.
  • Repeated shapes. .lbrn2 can store a shape's points once and let copies refer to them by number, which saves a lot of space in files with arrays of identical parts.

The result is that .lbrn2 files are much smaller and faster to load, which is why LightBurn made them the default.

Which should you send?

Send .lbrn2 unless the person on the other end has a very old copy of LightBurn. If they don't have LightBurn at all, send an SVG as well, or point them to this page so they can open the .lbrn2 themselves.

Opening either one here

Both formats open in the viewer above, with the same layer table, size, counts and exports. Older .lbrn files often come from LightBurn's early versions, and they write out every setting, so the table shows real values rather than defaults.

What about .lbt?

LightBurn also uses .lbt for templates. The viewer will open one if it holds a normal LightBurn project inside. If it doesn't, you'll see a plain explanation instead of a blank page.

Layers and settings

In the order LightBurn runs them. Untick a layer to hide it here and leave it out of exports.

Layers in this project with their cut settings
ShowLayerModeSpeedPowerPassesIntervalShapesPath lengthTime, est.

Grey italic values aren't saved in the file. A .lbrn2 leaves out values that match LightBurn's defaults, so the documented defaults are shown (100 mm/s, 20% power, 0.1 mm interval, one pass). Speeds are stored in mm/s; hover a speed for mm/min. Times assume the head always moves at full speed, so real jobs take longer; see how they're worked out.

Export

Only the layers that are switched on are exported. Files are made in your browser.

Free

SVG

For Inkscape, Illustrator, xTool Creative Space, the Glowforge app and LightBurn itself. Layers become groups in LightBurn's colours, at real size in millimetres.

Fill layers as

Unlock

DXF

For CAD, CNC routers, cutting services and older laser software. R12 DXF, one DXF layer per LightBurn layer, millimetres, true circles. Pictures can't go in a DXF, so they're left out.

Part of the £6 unlock, coming soon.

Free

Pictures

Images embedded in the project, and the preview LightBurn saved with it, can be saved as PNG files on their own.

See the pictures

Pictures in this file

Shown at their own size. The original file name is what the designer's computer called the picture.

Job sheet

One printed page for whoever runs the laser: the design, every layer's settings, sizes, and the time estimate with its assumptions. Choose Save as PDF in the print window for a file.

Printing the job sheet is part of the £6 unlock, coming soon. The preview is free to look at.

One-time unlock

DXF, batch conversion and job sheets

Viewing, inspecting and SVG export are free and stay free. The unlock adds the things that save a workshop time.

  • DXF export of any project, layer by layer.
  • Batch conversion: drop many .lbrn2 files, or a ZIP of them, and get one ZIP back with SVG and DXF for each, plus a CSV of every layer's settings.
  • Printable job sheets with settings, sizes and time estimates.
  • One payment, no account, no subscription. Your files still never leave your computer.

£6 once

Coming soon

It isn't on sale yet, so there's nothing to pay today. Everything free on this page works now.

How sure is each number?

Read straight from the file

Layer names, modes, speeds, powers, passes and intervals are exactly what the file says, apart from values shown in grey italics, which the file leaves out and LightBurn fills with its defaults. Shape counts are exact.

Measured from the shapes

Sizes and path lengths are measured from the geometry, with curves followed to within a few thousandths of a millimetre. Text without a saved outline has no exact shape, so it isn't measured, and you'll see a note when that happens.

Estimated, and labelled

Times assume the head always moves at the layer's speed. Lines take length × passes ÷ speed; fills sweep each row from the first edge to the last at the line interval; images scan their whole frame. Acceleration, overscan and travel aren't counted, so real jobs take longer, sometimes a lot longer.