Is it free to convert between OBJ and STL?

Yes, Convert999 is 100% free. All conversions happen locally in your browser with no file size limits, no registration, and no watermarks.

.obj

.stl

OBJ vs STL

Compare Wavefront OBJ and Stereolithography formats — understand the key differences and when to use each

Format Overview

OBJ

Wavefront OBJ

Wavefront OBJ (.obj) is a 3d file format.

.obj3d

STL

Stereolithography

Stereolithography (.stl) is a 3d file format.

.stl3d

OBJ vs STL: Feature Comparison

Feature	OBJ	STL
Full Name	Wavefront OBJ	Stereolithography
File Extension	.obj	.stl
Category	3d	3d
Free to Convert	✓ Yes	✓ Yes
Browser Support	✓ All Browsers	✓ All Browsers
Convert to Each Other	✓ Yes	✓ Yes

When to Use OBJ vs STL

Use OBJ when you need:

•Files in Wavefront OBJ format for maximum compatibility
•Industry-standard 3d format support
•Wide software and platform compatibility

Use STL when you need:

•Files in Stereolithography format for specific workflows
•Optimized 3d format features
•Modern format advantages and smaller file sizes

Convert Between Them

OBJ STL STL OBJ

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Learn More About These Formats

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Frequently Asked Questions

What is the difference between OBJ and STL?

OBJ (Wavefront OBJ) and STL (Stereolithography) are both 3d file formats. OBJ files use the .obj extension while STL uses .stl. They differ in compression, quality, compatibility, and intended use cases.

Can I convert OBJ to STL for free?

Yes! Convert999 lets you convert OBJ to STL completely free, directly in your browser. No file upload to any server, no registration needed — your files stay private on your device.

Which is better, OBJ or STL?

It depends on your use case. OBJ (Wavefront OBJ) may be better for certain workflows, while STL (Stereolithography) excels in others. Consider factors like file size, quality, software compatibility, and your specific needs.

Is it safe to convert files on Convert999?

Absolutely. Convert999 processes all files 100% locally in your browser. Your files are never uploaded to any server, ensuring complete privacy and security.

OBJ Converter

Convert from OBJ

STL Converter

Convert from STL

File Tools

Compress, resize, merge

Convert to OBJ

All sources → OBJ

Convert to STL

All sources → STL

Format Statistics

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More Format Comparisons

JPGvsPNG PNGvsWEBP JPGvsWEBP SVGvsPNG HEICvsJPG BMPvsJPG TIFFvsJPG GIFvsPNG

Feature

OBJ

STL

Full Name