Last updated: April 2025 — This guide has been fully revised with the latest advice on Windows ICO sizes, icon design best practices, and tools.
Designing a great-looking Windows icon doesn’t have to be complicated, but getting it right matters more than ever. Whether you’re building a Windows desktop application, packaging an installer, or just want your shortcut icon to look sharp on any Windows device, a properly built .ico file is still essential for modern Windows applications. In this icon design guide, we’ll break down everything you need to know, from icon sizes and formats to smart tools and professional tips.
🧰 What’s the Minimum I Need to Create a Windows Icon?
- ✅ One high-quality PNG image at 256×256 pixels
- ✅ 32-bit colour depth with transparency (alpha channel)
- ✅ Use a tool like IconWorkshop to convert it to a
.icofile
This single image will allow Windows to scale the icon for most uses, desktop, taskbar, file explorer, etc. But here’s the catch: Windows doesn’t scale down images well, especially to small sizes like 16×16. This often leads to blurry or pixelated icons that undermine your app’s look and feel.
Want it to look great at all sizes? You’ll need to create separate, pixel-perfect versions for the key icon sizes. That’s where a professional Windows icon designer comes in.
👉 See the difference in our post: Icon Maker Software Review – Dumb Scaling vs Pro Design
👇 What Is a Windows ICO File?
A .ico file is a special container format used by Windows to store multiple versions of an icon at different sizes and colour depths. This allows the operating system to choose the best icon version depending on the context — for example, a large 256px icon for Windows Explorer or a tiny 16px icon for system tray use.
Each version inside the .ico file is called a sub-image, and it’s typically stored as a BMP or PNG format with a specific pixel dimension and colour depth.
📐 Default vs Optional Windows ICO Sizes
| Size (px) | Required? | Purpose |
|---|---|---|
| 16×16 | ✅ Yes | Toolbar icons, favicons |
| 24×24 | 🔘 Optional | Smaller menus or UIs |
| 32×32 | ✅ Yes | Classic desktop icon size |
| 48×48 | ✅ Yes | Standard explorer size |
| 64×64 | 🔘 Optional | Windows 7/10 higher-res |
| 128×128 | 🔘 Optional | HiDPI screens |
| 256×256 | ✅ Yes | Modern icons and scaling |
Tip: For best results, include at least 16, 32, 48, and 256px versions — all saved as 32-bit PNGs with transparency.
Older systems used 8-bit or 24-bit BMP icons (without alpha transparency), but modern Windows supports full 32-bit alpha-enabled icons.
Viewing ICO File Sizes in Windows Explorer
To inspect the different sizes embedded within an ICO file:
- 🔹 Save your ICO files into a folder.
- 🔹 Use the ‘View’ dropdown to select various icon sizes.
- 🔹 Windows will automatically scale the icons as you adjust the view settings.
It’s easy to check your Windows ICO file sizes in Windows 11
🖼️ Why One Icon Doesn’t Fit All
Here’s the real problem: Windows will happily take your 256×256 PNG and auto-scale it down to 16×16… but the result will almost always be blurry or unreadable. Small icons require a completely different design approach, fewer details, bolder shapes, and higher contrast.
We often compare this to designing logos: a detailed logo might look fantastic on a poster, but shrink it down to fit on a pen and it becomes a smudge.
That’s why professional icon designers manually create each key size, ensuring your icon looks sharp at any resolution, especially in industries like CAD, medical, or data-heavy applications where clarity matters.
🛠️ Tools to Build and Test ICO Files
🏆 IconWorkshop – Our Favourite
- 🔹 Drag-and-drop multiple PNGs
- 🔹 Built-in editing tools for tweaking individual sizes
- 🔹 Supports alpha transparency and legacy formats
- 🔹 Batch export capabilities
If you’re serious about icon design, IconWorkshop is worth every penny. It’s been around for years and is used by countless professional designers, including us.
Axialis Icon Workshop ICO editor and icon design tool
🧩 Other Alternatives
- 🔹 GIMP or Photoshop (with plugins): Great for editing, but ICO export requires plugins or workarounds
- 🔹 IcoFX: Budget-friendly alternative with decent editing tools
- 🔹 Online converters: Fast and easy, but often lacking in quality and transparency support
🧑💼 When to Use a Professional Designer
If you care about your software’s polish, user experience, and brand perception, a professionally designed icon is a smart investment. Here’s why:
- 🔹 Precision matters: 16×16 icons need completely different layouts than 256×256
- 🔹 Brand consistency: Custom icons reinforce your visual identity across platforms
- 🔹 Performance: Optimised icons reduce visual noise and cognitive load
- 🔹 Compatibility: We ensure your icons work across all Windows versions
You may think just exporting your company logo is good enough, but remember, choosing a good Windows Icon Designer is not just about the quality and crispness of the ICO file itself, but the entire custom icon design process. From concepts to delivery, you’ll see ideas you never imagined, so it’s well worth the investment.
🚀 Large Projects? Use Our Icon Manager Tool
Managing 50 or 500 icons across multiple apps? Our custom-built Icon Manager platform helps you:
- 🔹 Upload and manage all icons in one place
- 🔹 Automatically combine PNGs into ICO files
- 🔹 Preview icons at all sizes
- 🔹 Comment, approve, and download files instantly
🍏 What About macOS Icons?
macOS uses a similar format called .icns, which also supports multiple sub-images and transparency. It’s typically used for Mac app icons and follows its own export process. We support both formats — just ask!
✅ Summary: What You Need to Know
- 🔹A 256×256 PNG is the minimum needed, but won’t look good at small sizes without custom design
- 🔹A full ICO should include multiple sizes: 16, 32, 48, and 256px
- 🔹Use IconWorkshop to build and test your ICO
- 🔹For pro results, each size should be designed individually
- 🔹Icon Manager can help automate this for large projects
✋ Ready to Look More Professional?
You’ve got two options:
- 🔹DIY: Create a 256×256 PNG and convert it using IconWorkshop. It’ll work, just don’t expect pixel-perfect clarity at small sizes.
- 🔹Work with a Pro: Let us create a fully optimised ICO file with pixel-perfect artwork for every key size. Learn more about our custom icon design services.
Talk to Adam today for a no-obligation chat about your icon needs.
