How do I open a .CUI file on Windows or Mac?

You can open .CUI files using Universal File Inspector, Native CAD & 3D Viewer, OpenAnyFile Browser Viewer. If you do not have native software installed, you can use OpenAnyFile's free File Identifier or convert .CUI to a standard format in your browser.

Is a .CUI file safe to open?

This format carries a safety rating of Low Risk. Verify the .CUI extension in OS File Explorer before opening Inspect magic byte signature to ensure file is not a renamed executable Run anti-malware scan on files downloaded from untrusted sources

Can I convert a .CUI file to other formats?

Yes! .CUI can be converted to formats such as .JPG, .WORD, .JPG directly in your web browser.

What should I do if a .CUI file is corrupted or won't open?

If your .CUI file displays an invalid header or signature error, check its magic bytes hex header (Varies) using OpenAnyFile's Magic Byte Detector or follow our step-by-step file repair guide.

How do I open .CUI files?

You can open .CUI files using Universal File Inspector, Native CAD & 3D Viewer, OpenAnyFile Browser Viewer.

CAD & 3D • MIME: application/x-cui

.CUI – CUI File Format

Q: What is a .CUI file?

A .CUI file is a CUI File Format associated with CAD & 3D. Learn everything about .CUI (CAD & 3D) file extension. Discover software tools to open .CUI files on Windows, macOS, Android, and iOS, convert online, and check file header security.

Learn everything about .CUI (CAD & 3D) file extension. Discover software tools to open .CUI files on Windows, macOS, Android, and iOS, convert online, and check file header security.

Primary Category CAD & 3D

MIME Type application/x-cui

Magic Bytes Signature Varies

Security Risk Rating Low Risk

Recommended Software to Open .CUI

Universal File Inspector

windows, mac, linux • Free

Native CAD & 3D Viewer

windows, mac, linux • Free

OpenAnyFile Browser Viewer

windows, mac, linux • Free