Favicon Sizes Explained (16–256): What to Include in favicon.ico
Know exactly which icon sizes belong in your favicon.ico and why each one matters
Convert NowWhere Favicons Actually Show Up
Most people think of favicons as the tiny icons in browser tabs, but they appear in far more places than that. Understanding every context helps you choose which sizes to include so your icon always looks sharp.
Browser tabs are the most visible location. Every open tab displays your favicon at roughly 16 pixels, making it the primary way users identify your site when many tabs are open. Bookmark bars and menus also render your icon at 16 pixels in most browsers, so a crisp version at this size is non-negotiable.
Address bars and search suggestions in some browsers show the favicon beside the URL, typically at 16 or 32 pixels depending on the display density. History panels behave similarly, pulling the favicon to help users scan through previously visited sites.
Beyond the browser, favicons appear in operating system contexts as well. When a user pins your site to the Windows taskbar or creates a desktop shortcut, the OS pulls from the ICO file and may render the icon at 48, 64, or even 256 pixels. On high-DPI (Retina-class) displays, a 32-pixel icon may be stretched to fill a space that demands more detail, producing a blurry result unless a larger variant exists inside the ICO.
Progressive Web Apps (PWAs) use their own manifest icons rather than favicon.ico, but the favicon still matters as a fallback for standard browser chrome and for users who bookmark the site without installing the PWA.
What Each Favicon Size Is For
Each pixel dimension serves a distinct purpose. The table below maps every standard favicon size to its common use and indicates whether you should include it.
| Size (px) | Common Use | Include? |
|---|---|---|
| 16 × 16 | Browser tabs, bookmarks bar, address bar, history | Yes — required |
| 32 × 32 | High-DPI browser tabs, Windows taskbar, macOS Safari | Yes — required |
| 48 × 48 | Windows site-pinned shortcuts, Windows Explorer | Yes — recommended |
| 64 × 64 | Some Windows UI surfaces, RSS readers | Optional |
| 128 × 128 | Windows large-icon view, Chrome Web Store | Optional |
| 256 × 256 | Windows extra-large view, high-DPI desktop shortcuts | Recommended for completeness |
16 and 32 pixels are the absolute essentials. Without them, browsers fall back to a generic globe or blank icon, which hurts brand recognition. These two sizes cover virtually every standard-DPI and high-DPI browser tab scenario.
48 pixels enters the picture when users create Windows shortcuts to your site. The operating system renders desktop shortcuts at 48 pixels in the default icon view, so including this size prevents the OS from awkwardly upscaling the 32-pixel variant.
64 and 128 pixels appear in niche contexts. Some Windows UI surfaces and third-party applications request a 64-pixel icon, while 128 pixels is used by the Chrome Web Store and certain large-icon views. Including them adds only a few kilobytes to the ICO file, so the trade-off is minimal.
256 pixels matters most on high-DPI monitors. When Windows renders an extra-large icon view or a user pins your site to the taskbar on a 4K display, the OS may pull the 256-pixel variant for the sharpest possible rendering.
The Recommended Safe Set
If you want a single favicon.ico that covers the broadest range of contexts without unnecessary bloat, use this safe set:
- 16 px — browser tabs and bookmarks
- 32 px — high-DPI tabs and Windows taskbar
- 48 px — Windows desktop shortcuts
- 256 px — high-DPI and extra-large icon views
This four-size set keeps the ICO file compact (typically under 30 KB) while ensuring sharp rendering in every major context. You can add 64 and 128 pixels if your use case demands it, but most websites will never notice a difference.
If you are building a favicon purely for the web and do not expect users to create desktop shortcuts, you can trim the set down to just 16 and 32 pixels. That produces an ICO file well under 10 KB. However, the cost of including 48 and 256 is so small that we recommend the full safe set as the default for nearly every project.
For a broader look at how the ICO format works and when it is the right choice over PNG, see our explainer on what an ICO file is.
How to Generate the Right Favicon Sizes
Creating a multi-size favicon.ico takes just a few steps with Any2ICO. The tool accepts PNG, JPG, WebP, GIF, BMP, AVIF, and SVG source images up to 10 MB, and it produces a properly structured ICO file containing every size you select.
- Start with a high-resolution source. Upload your logo or icon at 512 pixels or larger. A large source gives the converter enough detail to produce clean, downscaled versions at every target size. SVG sources work especially well because they scale without any loss of detail.
- Select your sizes. Check the boxes for 16, 32, 48, and 256 (the safe set), or add 64 and 128 if you need them.
- Choose scaling behavior. Contain fits the image inside each square while preserving the aspect ratio, padding any extra space. Cover fills the entire square, cropping edges if necessary. For most logos, contain with a transparent background is the best choice.
- Download your favicon.ico. Place the resulting file at the root of your website (
https://yoursite.com/favicon.ico). Browsers look for this path automatically, so in many cases you do not even need a<link>tag.
Any2ICO performs the conversion directly in your browser using the Canvas API. Files imported from your device are transmitted through the server for processing but are not stored. Clipboard pastes stay entirely on your machine. If you are converting several icons at once, the batch mode lets you download everything in a single ZIP file.
For a complete walkthrough with screenshots and HTML code snippets, see our step-by-step guide on how to create a favicon.ico. And if you need to convert a PNG specifically, our PNG to ICO guide walks through that workflow in detail.
Wrapping Up
Choosing the right favicon sizes does not have to be complicated. The core rule is simple: always include 16 and 32 pixels, add 48 and 256 for Windows and high-DPI coverage, and use a high-resolution source image to keep every size sharp. That four-size safe set handles the vast majority of real-world scenarios.
When you are ready to build your favicon, Any2ICO makes it easy. Upload your image, pick your sizes, and download a single ICO file that works everywhere. It is free, fast, and respects your privacy.