How to Convert BMP to G-code Free, Step by Step

Why convert BMP to G-code?

A G-code is motion commands a controller runs directly: move here, at this speed, with the tool on. No interpretation left. The machine does exactly what the file says.

Laser cutting and engraving.
CNC routing.
Sending straight to the controller.

The catch is the BMP itself. Enormous. A 4000 by 3000 image is 36MB, where a PNG of the same picture might be 2MB. That is why the conversion matters as much as the file you start with.

Where most converters let you down

Plenty of tools will happily take your BMP and give you something back. The trouble is what they give you: many write coordinates in pixels with no units, upside down, with outlines that do not close. You only find out later, when the file will not cut, print, import or open the way you expected.

What you actually want is machine geometry in real millimetres or inches, the right way up, with closed contours. That is the standard this BMP to G-code converter is built to.

How to convert BMP to G-code in 3 steps

Open the BMP to G-code converter and drop in your BMP.
Check the result in the preview and adjust the settings if you need to.
Download the G-code.

Convert BMP to G-code now

Why Veconvert is the better BMP to G-code converter

Real units in the file. G-code output carries millimetres or inches, so it imports at the size you set.
The right way up. Image coordinates run downwards; machine coordinates run upwards. The conversion flips them so the part is not mirrored.
Closed contours. Outlines join up, and anything that does not is flagged before you download.
Preview the machine file itself. The download is parsed back and drawn, so what you see is what the machine will get.
Nothing uploaded. Drawings for clients stay on your machine.

What happens to your file

Your BMP is first traced in the browser into clean outlines. For a machine the trace is set up for cutting rather than colour: one outline where a cutter should go, with photos turned into line art instead of blotchy shapes.

The conversion runs in your browser, so the file is never uploaded: client work, statements and unreleased designs stay on your computer.

Getting the best G-code: mistakes to avoid

BMP is uncompressed, so it is usually a clean source; just check it is not a tiny icon-sized image.
High-contrast BMP artwork gives the cleanest toolpaths: dark shapes on a light background.
Set the finished width in the settings before downloading, then check the size the page reports.
For a laser, decide whether each shape should be cut or engraved in your laser software; the file gives you clean outlines for either.
Run a test cut on scrap before cutting good material, as you would with any new file.

What it costs

Yes, converting is free: the conversion and checking the result cost nothing, and the work runs in your browser, so nothing is uploaded. The side-by-side preview on the converter pages comes with a free account. Saving the finished file is paid: $3.49 for one file ($3.99 for a technical file such as DXF, G-code, STL or embroidery) with no account needed, or included in a plan from $6.99 a month.

You see the result before you spend anything, so you only pay for a file you are happy with.

Frequently asked questions

How do I convert BMP to G-code?

Drop your BMP file on this page, check the preview, and press Download. The G-code is made in a few seconds, with no sign-up.

Is my BMP file uploaded anywhere?

No. The bmp to g-code conversion runs in your browser, on your own device. The file never leaves it.

What units does the G-code use?

Millimetres or inches, whichever you choose. The size you set is the size the machine cuts.