Image Format Comparison

ICO vs CUR — Windows Icon vs Windows Cursor

ICO and CUR are nearly identical Windows formats — both store one or more bitmap images at multiple resolutions. The only meaningful difference is that CUR (cursor) files include a 'hotspot' coordinate specifying which pixel triggers clicks. ICO files are for icons; CUR files are for mouse cursors.

ICOvsCUR

Quick Verdict

Use ICO when…

Use ICO for application icons, file type icons, and favicons. Standard Windows iconography uses ICO files at multiple resolutions (16, 32, 48, 256 pixels).

Use CUR when…

Use CUR for custom mouse cursors. CUR is required when you want a clickable hotspot — the pixel that triggers click events. For animated cursors, use ANI (Animated Cursor) format.

ICO vs CUR: Feature Comparison

Feature	ICO	CUR
Purpose	Application/file icons	Mouse cursors
Hotspot field	No	Yes (X, Y coordinates)
Multi-resolution	Yes (multiple sizes in one file)	Yes
Bit depth	Up to 32-bit RGBA	Up to 32-bit RGBA
Animation	No	ANI variant for animated cursors
Cross-platform	Windows, Linux	Windows only (mostly)

When ICO wins

✓Purpose: Application/file icons
✓Hotspot field: No
✓Multi-resolution: Yes (multiple sizes in one file)

When CUR wins

✓Purpose: Mouse cursors
✓Hotspot field: Yes (X, Y coordinates)
✓Multi-resolution: Yes

Frequently asked questions

Can I use an ICO file as a cursor?

Not directly — Windows expects CUR for cursors and uses the hotspot field. You can rename .ico to .cur, and Windows will assume hotspot 0,0 (top-left), but click accuracy will be off. Convert properly using a tool that sets the hotspot.

How do I convert ICO to CUR?

Use IcoFX, GIMP, or Greenfish Icon Editor. Open the ICO, set the desired hotspot pixel, and save as .cur. The file structure changes from icon-type to cursor-type and the hotspot coordinates are written into the header.