STL File Type

- The quick facts

What are STL files and how to open them

Are you having problems opening a STL file or just wondering what they contain? We explain what these files are used for and show you software that we know can open or otherwise handle your files.

What is a STL file?

STL files have multiple uses, and Stereolithography CAD is one of them.

Stereolithography CAD File

This file format was developed by Albert-Battaglin Consulting Group for the company 3D Systems back in 1987. It is a file format used in stereolithography Computer-Aided Design (CAD) systems. Stereolithography (SLA) is an industrial 3D printing process used to rapidly create concept models, prototypes, and complex parts.

The STL file format is supported by many CAD software packages and is used for prototyping, computer-aided manufacturing, and 3D printing projects. It describes the 3D object in its most basic form and does not include color information, textures, or other attributes used in other 3D file formats.

Several non-standard STL derivations exist.

How to open STL files

We have identified 8 STL openers that are compatible with this specific type of STL file.

Programs that open Stereolithography CAD files

3D Studio Max3D Studio MaxVerified
Alibre DesignAlibre DesignVerified
Autodesk NetfabbAutodesk NetfabbVerified

Last updated: June 29, 2022

All known file formats using extension .STL

While Stereolithography CAD File is a popular type of STL-file, we know of 8 different uses of the .STL extension. Different software may use files with the same extension for different types of data.

SuperTux Level

We know that one STL format is SuperTux Level. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

STL opener for Windows

We have identified one STL opener that is compatible with this specific type of STL file.


More file formats using the STL extension

Through our research of STL files, we know that the following formats exist. However, we have not yet analyzed them in detail.

  • Certificate Trust List
  • EBU Subtitling Data Exchange Format
  • KISSSlicer STereoLithography
  • OpenSCAD STereoLithography
  • SkyOS Style
  • Spruce Subtitles

Various apps that use files with this extension

These apps are known to open certain types of STL files. Remember, different programs may use STL files for different purposes, so you may need to try out a few of them to be able to open your specific file.

FireworksFireworksUser submitted
Cadence Design System StmedCadence Design System StmedUser submitted
PSpice Stimulus EditorPSpice Stimulus EditorUser submitted
CuraCuraUser submitted
Jubler Subtitle EditorJubler Subtitle EditorUser submitted
Stimulus EditorStimulus EditorUser submitted
netfabb Studio Basicnetfabb Studio BasicUser submitted
MagicsMagicsUser submitted
Subtitle WorkshopSubtitle WorkshopUser submitted

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