Convert Your 3D Mesh/Model OFF Files to STL

Our free and fast tool will convert most 3D mesh or OFF (Object File Format) model files to a standard STL (Standard Triangle Language) file that can then be edited further in most popular 3D editing packages such as Blender or 3D printed without any further processing. Our conversion tool can also batch convert multiple OFF files; up to 25 files at a time can be converted.

To convert your OFF file, click the Upload button above and select the file to convert. Once selected, the file will be converted to a STL file and will be ready for download shortly afterwards. For more information about the OFF to STL conversion process, see the conversion information section below.

How to Convert your OFF to STL Online?

Here are two simple steps to convert your OFF to STL.

Upload a OFF

Click the "Upload a OFF File" button and select a OFF to upload. The maximum file size is 100MB.

Download your STL

Click the download link once completed to receive your STL file.

Frequently Asked Questions

How can I convert my OFF file to STL?

First click the "Upload..." button, select your OFF file to upload. Select any configuration options. When the OFF to STL conversion has completed, you can download your STL file straight away.

How long does it take to convert my OFF to STL?

We aim to process all OFF to STL conversions as quickly as possible, this usually takes around 5 seconds but can be more for larger more complex files so please be patient.

How accurate is the OFF to STL conversion?

We aim to create the most accurate conversions with our tools. Our tools are under constant development with new features and improvements being added every week.

Is it safe to convert my OFF to STL on ImageToStl.com?

Yes, of course! We do not store the OFF file you submit to us. The resulting STL file, once created is deleted 15 minutes after upload and the download link will expire after this time.

Can I convert OFF to STL on Windows, Linux, Android, iOS or Mac OS?

Yes! Our OFF to STL tool will run on any system with a modern web browser. No specialist software is needed to run any of our conversion tools.

What if I am using an Ad Blocker, will that affect things?

Yes. Although you can use an Ad Blocker, if you like our OFF conversion tool please consider white-listing our site. When an Ad Blocker is enabled there are some conversion limits on some of our tools and processing/conversion times will be longer.

What STL formats can I convert to?

Our tool will save all STL files in binary format. Optionally, our tool will allow you to save to the non-standard color STL format.

I have several OFF files; can I batch convert my OFF to STL?

Yes! Our OFF tool supports full batch conversions. You can upload up to 25 and OFF files at a time. Our tool will convert them all as quickly as possible. Once completed, you can either download the STL files individually or download them all in a single ZIP file.

Comparing OFF and STL Features

OFF Features

Mesh Geometry (Vertices and Faces)
Vertex Normals
Face Normals
Vertex Colors
Face Materials (Excluding textures)
Textures
Point Cloud
Multiple Objects Per File
Object Transforms (Translation, Rotation, and Scale)
Bones/Joints
Animations
Suitable for 3D Printing

STL Features

Mesh Geometry (Vertices and Faces)
Vertex Normals
Face Normals
Vertex Colors
Face Materials (Excluding textures)
Textures
Point Cloud
Multiple Objects Per File
Object Transforms (Translation, Rotation, and Scale)
Bones/Joints
Animations
Suitable for 3D Printing

File Format Information for OFF to STL

Extension	OFF
Full Name	Object File Format
Type	3D Model
Mime Type	text/plain
Format	Text
Tools	OFF Converters, 3D Model Voxelizer, Create OFF Animation, Compress OFF, Text to OFF, OFF Viewer
Open With	MeshLab, CAD Assistant

Description

The OFF file format is a simple text-based format capable of storing 2D and 3D geometry and was originally developed for the Geomview application. There is also an extension to the OFF format used by the Stella4D application to enable the storage of four-dimensional data.

The format can contain common vector information such as vertices, faces, shapes, and edge information, and it also has support for including color information. As the format is text-based, the files can become rather large, with no built-in compression options available.

OFF Notes

If your STL file contains face colors, these will be imported and mapped where possible.

Supported Features

Mesh geometry
Face colors

Extension	STL
Full Name	Standard Triangle Language
Type	3D Model
Mime Type	application/vnd.ms-pki.stl
Format	Text & Binary
Tools	STL Converters, 3D Model Voxelizer, Create STL Animation, Compress STL, Text to STL, STL Viewer
Open With	Blender, Daz Studio, MeshLab, CAD Assistant

Description

The STL file format has its roots in the 1980's and is the native file format for 3D Systems stereolithography CAD software. The format defines a triangulated mesh with vertices and faces and is a popular format for sharing 3D printable model files.

There were several formats that attempted to extend the STL format, namely SolidView and VisCAM, whose formats included limited 15-bit color information for each mesh face, which is often ignored by most modern 3D software. The STL format can be either text or binary; our tools will support both formats.

STL Notes

The standard STL file format does not support colored faces, vertices, or texture information. The STL file generated by the tool will contain only raw mesh/triangle data by default, which is perfect for 3D printing.

The tool also has the option to save the file to one of the non-standard formats that support colored faces, such as VisCAM and SolidView which is perfect if you want to further process the STL in software that supports these formats.

Supported Features

Mesh geometry
Face colors via the VisCAM and SolidView formats
Binary and text versions are supported

Converting Your OFF File for 3D Printing

Software used to prepare a 3D model file for printing, which is also known as 3D slicer software, cannot usually open OFF files. This is because slicer software authors will support the most common formats used for 3D printing, such as STL and 3MF and do not have the resources to implement 3D object parsers for all the possible 3D formats that are out there.

A small cog in the OFF format

The cog in a Replicator 3D printer

The completed 3D printed cog

Slicer software can, however, handle files formatted to the STL specification. This is because STL, although predating the 3D printing revolution and lacking in some of the features of modern formats, has found almost universal adoption as the format of choice for distributing 3D printable models. Our OFF to STL conversion tool can convert your OFF file into an STL file suitable for loading into the 3D slicer software of your choice. As STL files do not support material colors or textures, our converter will not process these, resulting in a single STL file suitable for use with most 3D slicer software.

How does it work?

Converting from the OFF file format to STL can be a complex process, and any tool used for this conversion process needs to be able to handle a variety of data conversion tasks as well as identify any defects within the 3D model and fix them. Here we will explain the conversion process used by our tool to accurately convert your OFF file to a valid STL 3D model. Let's start with the conversion process, which involves the following steps:

Step 1: Read the Source OFF File

In its simplest form, an OFF file is a plain text file containing human-readable 3D data such as vertices, faces, normals, and more. When combined, these make up the 3D model you see on your screen.

For more information regarding the OFF file format, please see this great article that goes into a lot of detail explaining the OFF format.

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Step 2: Process File Data

With the OFF file data read, our tool generates an internal representation of the full 3D model and will attempt to fix any geometry issues encountered. Along with repairing any issues with the 3D model, the tool will remove any duplicated vertices and prepare the model for exporting to the STL format.

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Step 3: Saving to the STL Format

The STL format has been around for many years and has become not only a standard format for storing and transmitting 3D models but also a standard format for 3D printing, something we have talked about previously. STL files can be opened in most modern 3D editing applications without further processing.

To enable the saving of the model, our tool now needs to take the in-memory 3D model we have created in step 2 and convert this to the STL format. As the STL format supports only simple triangles with a single directional normal, if your OFF contains vertex normals, these will be recalculated into a single-face normal. To ensure an efficient file size, our tool will always save any STL file in its binary format.