Browser-local converter
PNG to STL converter
Turn a PNG into a 3D relief you can print. Brightness becomes height by a stated rule: white is high, black is low, and you set exactly how tall the relief and its base are. This is a relief, not a reconstruction of whatever the picture shows.
Drop your PNG files here
STL, OBJ, PLY, GLB, glTF, 3MF, SVG and DXF, plus PNG and JPG as height relief. Nothing is uploaded: files are read and converted inside this tab. Checking what this device can handle...
Queue
No files yet. Drop models above, or use the file picker.
Output
Units
Size and placement
Repair and cleanup
These can change the shape, so they need a before-and-after review before export.
Inspection
Add a model to see its dimensions, mesh health and estimated volume.
What this PNG to STL conversion does and does not do
- This produces a height relief, not a 3D model of the object in the picture. A photograph of a chair becomes a bumpy plate whose height follows the brightness of the photo. Nothing in an ordinary photograph records the shape behind it, so nothing here can recover it.
- You set the relief height, base thickness and physical width in millimetres. The values shown are a workable starting point, not a measurement of anything in your image: an image records no depth, so these numbers are your decision.
- The image is resampled onto a grid, and both the grid and the resulting triangle count are shown before you convert. Full resolution on a 4000 by 3000 photo would be roughly 24 million triangles.
- Height comes from Rec. 709 luminance, so colour hue does not matter, only how light or dark each pixel is. A fully transparent pixel counts as the lowest level, so a cut-out PNG does not raise a plateau over empty space.
- The result is a closed solid: a top surface, a flat underside and a skirt joining them. It is watertight by construction and the inspection panel confirms it.
- Photographs generally make poor reliefs. A high-contrast greyscale image, a logo or a heightmap exported from terrain software gives a far better result than a snapshot.
Troubleshooting
The relief is much too shallow or too deep
Change the relief height. The value it starts at is a workable default, not something measured from your image, because an image carries no depth information at all.
The relief looks like noise
That is usually a photograph rather than a heightmap. Convert it to greyscale and raise the contrast first, or reduce the detail setting so fine variation is averaged out.
My engraved artwork is raised instead of cut in
Turn on invert. Artwork drawn dark-on-light needs dark treated as high, which is the opposite of the default.
The triangle count is enormous
Lower the detail setting. The panel shows the sampled grid and triangle count before you convert, so you can see the cost before paying it.
Questions
Will this turn a photo of an object into a 3D model of it?
No, and nothing can from a single ordinary photo. This maps brightness to height, which is a real and useful transform for lithophanes, terrain, engraving and textures, but it is not depth recovery. Any tool that claims otherwise is inventing geometry.
Is it good for lithophanes?
Yes, that is the classic use. Invert so dark areas become thick, keep the relief shallow, and check the result in your slicer at the wall thickness your printer actually resolves.
Which image formats work?
PNG and JPEG certainly, and in practice anything else your browser can decode, including GIF, BMP and WebP. Decoding uses the browser itself, so nothing is uploaded to read the image.
Is the STL watertight?
Yes, by construction: the top surface, the flat base and the skirt between them share every edge exactly twice. The inspection panel reports zero open edges, and the exported STL is re-opened and checked before download.