Introduction
If you’ve ever customized icons on your computer, you’ve likely encountered an ICO file. This format is essential for Windows icons, used for everything from desktop shortcuts to website favicons.
But what exactly is an ICO file, how does it differ from other image formats, and how can you create or convert one? Let’s dive in.
If you’re working with various vector and raster file formats, check out our previous guide on Vector Image File Types Explained for a breakdown of popular file types.
What is an ICO File?
An ICO file is a container format for one or more images of different sizes and color depths. Windows uses these files to display icons, ensuring that the appropriate resolution is used for different screen sizes.
Unlike PNG or JPG files, which store single images, an ICO file holds multiple sizes in one file, typically:
- 16×16 pixels (small taskbar icons)
- 32×32 pixels (desktop icons)
- 48×48 pixels (larger icons)
- 256×256 pixels (high-resolution icons for modern displays)
How to Open and Edit ICO Files
1. Using Windows and Mac Tools
- On Windows, you can preview ICO files with the default Photos app or Paint.
- On Mac, Preview won’t open ICO files natively, but you can convert them using online tools.
2. Using Design Software
Popular design programs like Adobe Photoshop, GIMP, and CorelDRAW can open and edit ICO files. However, Photoshop requires a plugin to handle ICO files.
If you’re a CorelDRAW user, you might also be interested in how to handle CDR files—check out our guide on Opening CDR Files: A Quick Guide.
3. Online Tools
For quick conversions, websites like ConvertICO, CloudConvert, or ICO Convert allow you to create, edit, or convert ICO files from PNG, JPG, or BMP.
How to Convert an Image to ICO Format
To create an ICO file from an existing image:
- Resize the image to standard icon dimensions (256×256, 128×128, etc.).
- Save or export as ICO in software like Photoshop or GIMP (with the right plugin).
- Use an online ICO converter if your software doesn’t support ICO exports.
ICO vs. Other Image Formats
| Format | Purpose | Transparency Support | Best For |
|---|---|---|---|
| ICO | Icons on Windows | Yes | Windows shortcuts, favicons |
| PNG | Web images | Yes | High-quality images, transparent backgrounds |
| JPG | Photos | No | Compressed images |
| SVG | Scalable vector graphics | Yes | Web and UI design |
Icons are often accompanied by typography in UI design. If you’re dealing with fonts and want to understand the differences between TTF and OTF, check out our post on TTF vs. OTF: Understanding Font Formats.
Final Thoughts
ICO files are small but powerful—allowing Windows to display icons correctly across different resolutions. Whether you’re designing a desktop app icon or a website favicon, understanding ICO files ensures your icons look sharp and professional.
If you’re working with different image formats for design, including raw camera files, you may find our next post useful: ARW File Type: What It Is and How to Open It.