About 3D Printer Wiki

3D Printer Wiki is an independent website with tools and guides for the files around 3D printing. It started from a simple observation: most of the time spent on a print isn't spent printing. It goes into getting the file right. A model arrives in the wrong format, at the wrong size, lying on its back, with holes in it, or as a CAD file the slicer can't open. Each of those problems has a fix, but the fix usually means installing a large program for a two-minute job. The tools here do those jobs directly in the browser, one job per page, with a guide that explains what happens and why.

What is on the site

The tools fall into six groups, which you'll find on the home page and in the footer of every page:

• Converters between print, CAD, art and web formats: STL, 3MF, STEP, OBJ, FBX, GLB, PLY, DAE, 3DS and IGES.
• Viewers that open those files on any device and show size, triangle count, parts and whether the mesh is a closed solid.
• Generators that make printable models from text, photos, logos, SVG and DXF drawings, QR codes and height maps.
• Exports from a 3D model to 2D: SVG and DXF sections and outlines, PNG pictures and depth maps.
• Fix and edit tools for repairing, scaling, reducing, splitting and rotating STL files.
• Calculators for volume, filament length and weight, and the full cost of a print.

How the tools work

Every tool is a small program that runs in your web browser. When you open a file, it is read from your device into the page, processed there, and the result is saved back to your device as a download. That's why the tools work the same on a laptop, a work computer where you can't install software, or a phone.

Reading files. Mesh formats such as STL, OBJ, PLY, FBX, GLB, DAE and 3DS are read with the loaders of three.js, a widely used open-source 3D library. 3MF files are read with a reader written for this site, because slicer projects from Bambu Studio, OrcaSlicer and PrusaSlicer store their meshes and filament colours in ways a plain 3MF loader doesn't handle. STEP, IGES and BREP files are read with Open CASCADE Technology, the open-source CAD geometry kernel that FreeCAD and many engineering tools are built on, compiled to run in the browser.

Units and orientation. Every model is converted to millimetres with Z pointing up, the way slicers and CAD programs work. Formats that store a unit, such as 3MF, STEP, DAE and glTF, are converted from that unit. Formats without one are read as millimetres, and the size line on every page shows the result so that a model in the wrong unit is easy to spot. Formats from games, animation and the web are turned from Y-up to Z-up.

Writing files. STL, 3MF, OBJ, PLY and STEP files are written by code made for this site. The STEP writer, for example, groups triangles that lie in the same plane into single faces with proper boundaries and holes, so a box comes out as six faces instead of twelve triangles, and a closed mesh becomes a closed solid in CAD. GLB files are written with the three.js exporter after the model is scaled to metres and turned Y-up, as the glTF standard requires.

Mesh tools. Repair welds matching corners, removes broken and duplicate triangles, turns flipped faces the right way, and fills holes. Reducing a file uses vertex clustering, which keeps the overall shape while lowering the triangle count. Sections for SVG and DXF are computed exactly from the triangles; whole outlines are traced on a fine grid.

Generators. Text is built letter by letter from font outlines. Lithophanes, image reliefs and height maps turn the brightness of each pixel into a thickness or height. QR codes are generated as a grid of modules and built as raised or recessed blocks. SVG and DXF drawings are read as closed outlines, with holes found automatically.

Calculators. Volumes come from the mesh itself, and weights from the volume, the shell thickness, the infill and the material density. Filament length follows from the weight, density and diameter. Print cost adds filament, electricity, an allowance for failed prints and machine wear, and optionally your time, markup and marketplace fees.

How the numbers are checked

Each tool opens with a sample file, and the numbers quoted in the guides were measured with the tools on those samples. A few examples: the sample gear, 1,104 triangles as STL, becomes a closed STEP solid with 274 faces, and the STEP file drops from about 724 KB to 300 KB when flat areas are merged. One kilogram of 1.75 mm PLA at 1.24 g/cm³ is about 335 m of filament. A 50 g, three-hour print costs about $1.47 with the calculator's default prices. The damaged sample knot used on the repair page has 12 open edges, 400 flipped faces and one hole, and comes out as a closed solid.

Where a guide gives facts that don't come from the tools, such as the history of a file format, printer build volumes or how a slicer menu is laid out, they come from the format specifications and the documentation of the programs concerned. Software changes, so menus and options in slicers and CAD programs may move over time. If you find something that is out of date, please let us know.

Limits worth knowing

• Meshes are not CAD. An STL converted to STEP becomes a solid with flat faces, not an editable model with cylinders and fillets. Curved surfaces stay faceted.
• Colour and texture. STL stores only shape. Textures from OBJ, FBX, GLB and PLY files are dropped; part colours can be kept in 3MF and GLB.
• Very large files depend on your device's memory. Models of a few million triangles open on a typical computer; phones handle less.
• Calculators estimate. Weight and cost estimates are close to what slicers report, but the slicer that prepares your print has the final word, because it knows your exact settings.
• Your models, your rights. The tools don't check licences. If you convert or print someone else's model, follow its licence, especially if you sell prints.

How the site is funded

The tools and guides are paid for by advertising. Ads are kept away from the tool boxes so they don't get in the way of your work. You can read how ads and statistics use cookies in the privacy policy, and the conditions for using the site in the terms of use.

Feedback and requests

Found a file that won't convert, a number that looks wrong, or a tool you wish existed? Write to hello@3dprinterwiki.org. A short description of the file, its format and the program it came from, the browser you use, and any message the tool showed usually makes it possible to reproduce the problem. Please don't send files you aren't allowed to share.

Updated November 2026 · How these tools work