It’s time to rethink how we cook a set of favicons for modern browsers and stop the icon generator madness. Frontend developers currently have to deal with 20+ static PNG files just to display a tiny website logo in a browser tab or on a touchscreen. Read on to see how to take a smarter approach and adopt a minimal set of icons that fits most modern needs.
The topic of favicons has proven to be more exhaustive than anyone could’ve ever wished, so I’ve also summarized the entire article in just two code snippets for those who’ve already suffered enough and who know exactly what to do. Still, I recommend geeking out to the rest of it!
The extremely short version
Instead of serving dozens of icons, all you need is just five icons and one JSON file.
That’s it. If you want to know how I got here, the compromises I had to make, and how to build a set like this from scratch in a step-by-step fashion, stay tuned in for the rest of the article.
The long version, where everything is explained
“Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.”
—Antoine de Saint-Exupéry, Airman’s Odyssey
The concept of a favicon, which is short for “favorite icon”, have been around since the early 2000s. We’ve all seen those cute little images in our browser’s tab bar which help us differentiate our open websites. Users expect your website to have a favicon. It’s one of those little things that make other people take you seriously.
Even Apple, which has always had some kind of aesthetic beef with icons that don’t come from Cupertino, downplaying favicons in Safari for years, has finally given up and now properly displays them across all of its devices.
If you have a public-facing website, it has to have a favicon. Sadly, what users perceive as one icon is actually a lot of them.
So, it’s common to offload the grueling task of generating these necessary files for an ever-growing list of screens and devices to favicon generator tools. No one in their right mind would ever want to spend hours creating them by hand. We’re here to build websites, after all, not to make browser vendors happy.
As a creator of NanoID and a proponent of minimalistic open source, I tend to think in a slightly different direction. What is the most efficient set of website icons? Which formats are outdated? Which icon types can be replaced with small compromises?
Thus, I set out to create a minimal list of favicons that will work in all cases and in all browsers—barring some edge cases—and even then, this will still work, just not 100% perfectly.
The Ultimate Favicon Setup
Instead of creating many images with different sizes, I decided to rely on SVG and browser downscaling. If you’re concerned about performance, I’m here to set the record straight:
Browsers download favicons in the background, so a bigger favicon image does not affect website performance.
SVG is a great way to reduce image size for images that aren’t supposed to be bitmaps in the first place; for many logos the resulting file will be much smaller than a PNG.
With just three PNG images in this minimum set, you can use advanced tools to optimize their size. This solves a problem for Internet users that don’t have unlimited data plans.
Now I’ll reveal the minimal set of icons that I came up with during my research and practice. This list should work with all popular browsers and devices, both old and new.
I. favicon.ico for legacy browsers
ICO files actually have a directory structure and can pack files with different resolutions. I recommend sticking to a single 32×32 image, unless the one you have doesn’t downscale well to 16×16 (if it becomes blurry, for instance). In that case, you can ask your designer to come up with a special version of the logo that’s tailored to fit small pixel grids.
Don’t get smart with the folder static asset folder structure and cache busters. https://example.com website should have a favicon on https://example.com/favicon.ico. Some tools, like RSS readers, just request /favicon.ico from the server and don’t bother looking elsewhere.
We need sizes="any" for <link> to .ico file in order to fix the Chrome bug where it chooses an ICO file over an SVG.
II. A single SVG icon with a light/dark version for modern browsers
SVG is a vector format that describes curves instead of pixels. At large sizes, it’s more efficient than raster images. As of this writing, 72% of all browsers support SVG icons.
Your HTML page should have a <link> tag in its <head> with rel="icon", type="image/svg+xml" and with the href containing a link to the SVG file as attributes.
SVG is an XML format and can contain a <style> tag to describes CSS. As with any CSS, it can contain media queries like @media (prefers-color-scheme: dark). This will allow you to toggle the same icon between light and dark system themes.
III. 180×180 PNG image for Apple devices
The Apple touch icon is an image that Apple devices will use if you add the webpage as a shortcut to your home screen on an iPhone or iPad. Your HTML page should have <link rel="apple-touch-icon" href="apple-touch-icon.png"> tag inside <head>.
Since iOS 8+, iPads have required an image with a 180×180 resolution. Other devices will downscale it, but if we provide the source with a high-enough quality, the downscaling won’t hurt the end-user (I’ll come back to this later).
Small note: an Apple touch icon will look better if you place 20px padding around the icon and add some background color. You can use any image editor to do this.
IV. Web app manifest with 192×192 and 512×512 PNG icons for Android devices
A web app manifest is a JSON file containing all the details for a browser to install your website as a system application. This format came about from Google via its PWA initiative.
Your HTML page should have a <link rel="manifest" href="path.webmanifest"> tag with a link to the manifest file.
The manifest should have an icon field that links to two icons: 192×192, for display on the home screen, and 512×512 which will be used as a splash screen as PWA is loading.
There are, of course, more favicon flavors out there, some of them quite obscure, so let’s see how our setup fares with them. Maybe, it’s time to say farewell to some of the less successful formats out there.
Windows Tile Icon
Microsoft Edge used to support a special icon format to pin websites to the start menu. For recent versions of Windows, this is no longer required.
Safari Pinned Icon
Safari formerly had a requirement of SVG monochrome icon for pinned tabs. However, since Safari 12, we can use a regular favicon for pinned tabs. Even apple.com doesn’t use the mask-icon anymore.
A lot of (now outdated) tutorials will include a favicon.ico into HTML like this:
Be warned that shortcut is not, and never has been, a valid link relation. Read this amazing article by Mathias Bynens from ten years ago that explains why we never needed shortcuts and why rel="icon" is just fine.
Yandex Browser is a Chromium-based browser from the biggest Russian search engine. In Russia, it has a 20% market share. It has a nice feature that allows a website to display live data in widgets on a home screen through a special JSON manifest provided by the yandex-tableau-widget link. However, this feature proved not to be very popular, and Yandex has now removed the corresponding technical documentation from its website. Regular icon manifests will work just as well.
In the past, Opera Coast, an experimental browser for iOS, required a special 228×228 icon. This browser left the App Store in 2017, and I doubt it survived the multiple iOS updates since that time.
Now, as we wave good-bye to our fallen comrades, let’s see how to produce an ultimate favicon set for those who are still standing.
How to build our Ultimate Favicon Set
Here’s how to build our ultimate, minimalistic favicon set in six quick steps. All you need to start is an SVG file for the logo that you want to use.
Step 1: Prepare the SVG
Be sure that the SVG image is square. Open the source file in your system viewer and check the image’s width and height. It’s easy to adjust the SVG size using any SVG editor. In Inkscape, you can change document size by selecting File → Document Properties and then center the logo using Object → Align and Distribute.
Save your file as icon.svg. Now let’s fiddle with our SVG and make it play well with modern system themes. Ask your designer how the colors should be inverted for a dark theme (for B&W logos, you just change black to white).
Now, open your SVG file in a text editor. Find a <path> with a dark or missing fill. Add a CSS media query that will trigger on theme changes and change fill to the colors you want:
Open your icon.svg file in a raster graphics editor. I recommend GIMP; it’s free and multi-platform.
Accept rendering SVG to raster. Set the width and height to be 32 pixels. Export file to favicon.ico using 32 bpp, 8-bit alpha, no palette settings.
If you do not have GIMP you can install Inkscape and ImageMagick and convert SVG to ICO in the terminal:
inkscape ./icon.svg --export-width=32 --export-filename="./tmp.png"# In Windows call `magick convert ./tmp.png ./favicon.ico`
convert ./tmp.png ./favicon.ico
Scale the image down to 16×16 and check the icon visibility. If it has become too blurry, it would be better to ask your designer for a custom tiny version of the logo.
To include a separate 16×16 version of an icon:
Open favicon.ico with the 32×32 icon.
Create a new layer with a 16×16 size.
Put the 16×16 version of an icon into this layer.
Export the file. GIMP will save each layout as a separate version of the icon.
Or you can do the same in ImageMagick by:
convert ./icon-32.png ./icon-16.png ./favicon.ico
Step 3: Create PNG images
Open your source SVG file in a raster graphics editor again and create a 512×512 image. Export it as icon-512.png. Scale the image to 192×192 and export it to icon-192.png. Now scale the image itself to 140×140 and set the canvas to 180×180, and then export it as apple-touch-icon.png.