How to Convert WebP to ICO for Website Favicon Optimization

Editor

Jul 31, 2025 • 7 min read

It’s easy to overlook that tiny image in your browser tab—the favicon. But this tiny square does more than just sit there looking pretty. It’s your site’s digital ID badge, branding signal, and first impression all rolled into one. Whether users have ten tabs open or are bookmarking your site for later, the favicon helps them recognize and return to your site.

Favicons aren’t just for show. They improve user experience, establish trust, and even impact SEO. When a website lacks a favicon, it feels unfinished or unprofessional. And on a subconscious level, that can erode credibility. When designed and implemented correctly, a favicon becomes a seamless part of your brand’s visual identity, much like your logo or color scheme.

Furthermore, favicons show up in search engine results, browser tabs, bookmarks, and mobile app shortcuts. And with the rising diversity of screen types, resolutions, and browser engines, having a properly formatted favicon isn’t optional—it’s essential. You want every pixel working for you, not against you.

The Rise of WebP and the Need for Conversion

WebP has surged in popularity as a modern image format thanks to its superior compression rates and excellent quality. Developed by Google, WebP provides both lossless and lossy compression, reducing file sizes without compromising visual fidelity. Naturally, designers and developers started adopting WebP for website images, including logos and favicons.

But here’s the catch: browsers haven’t caught up completely. While most modern browsers support WebP for content images, they don’t consistently support WebP as a favicon format. That means relying solely on WebP for your favicon could leave you invisible in many tabs, especially in older or less updated browsers.

That’s why converting your WebP favicon into ICO format becomes vital. The ICO format supports multiple image sizes and resolutions within a single file, ensuring that your favicon looks crisp on every platform, from old-school desktop browsers to high-resolution mobile displays.

ICO: The Unsung Hero of Cross-Browser Compatibility

Despite its age, the ICO format is still the most reliable standard for favicons. Why? Because it was specifically designed for the task. An ICO file isn’t just an image—it’s a container that can store multiple versions of your icon in different sizes (16x16, 32x32, 64x64, etc.). This makes it incredibly versatile for browsers to adapt the right resolution depending on the device and context.

What makes the ICO format stand out is its universal support. From Internet Explorer to the latest version of Chrome, ICO is recognized and rendered properly. It guarantees that your favicon will show up as expected, no matter the platform, providing a consistent brand experience.

So even if WebP is flashier and newer, it simply doesn’t deliver the cross-browser reliability that ICO does, especially where favicons are concerned. Most modern web practices still recommend including an .ico file at the root of your website. It’s tried, tested, and trusted.

I. Understanding the Basics

A. What is WebP?

WebP is a modern image format developed by Google to create smaller, richer images that make the web faster. Unlike older formats like JPEG or PNG, WebP supports both lossy and lossless compression, transparency (alpha channel), and animation—all in a single format.

This format can reduce image sizes by up to 25-35% compared to JPEG or PNG without noticeable quality loss. That makes it especially useful for website performance, where every kilobyte saved contributes to faster loading times and better SEO rankings. With more users browsing on mobile devices, speed isn’t just a luxury—it’s a necessity.

Use cases of WebP include:

Logos and header images on websites
Background images and banners
Product images in e-commerce
Blog featured images

However, WebP is still not fully supported in every context. Notably, specific browsers and platforms—especially older ones—do not recognize WebP as a favicon. And when your favicon fails to load, it doesn’t just look bad—it can confuse users or make your site seem outdated. That’s where conversion becomes essential.

B. What is an ICO File?

The ICO file format has been around since the early days of Windows. It’s a specialized image format created to serve icons across various contexts, from desktop shortcuts to browser tabs. What makes ICO files unique is that they can contain multiple sizes and color depths of the same image within a single file.

For favicons, this multi-resolution capability is incredibly valuable. When you create an ICO file, you’re essentially packaging a set of images (e.g., 16x16, 32x32, 48x48, 64x64, 128x128) into one container. This lets browsers and devices choose the best resolution based on where the favicon is displayed.

Why is ICO still the standard for favicons?

Universal browser support (even for legacy browsers)
Support for multiple sizes in one file
Recognized by Windows systems and older infrastructure
Preferred fallback format in <link rel="icon"> HTML tags

It might seem counterintuitive to use an older format in today’s web environment. However, when it comes to favicons, ICO still reigns supreme. It ensures that, regardless of the user’s browser or device, your branding remains consistent and visible.

C. Why You Can’t Just Rename WebP to ICO

Let’s be clear—file formats are not interchangeable just because you change the file extension. Renaming a .webp file to .ico is like sticking a Ferrari logo on a bicycle and expecting it to perform like a sports car. It doesn’t work that way.

WebP and ICO are fundamentally different in structure. WebP is a compressed image format optimized for speed and web performance. At the same time, ICO is a container format designed to hold multiple image resources in varying sizes and color depths.

If you try to rename a WebP file to ICO without proper conversion, the result will likely be:

A broken favicon that doesn’t render at all
Browser errors or fallback to default icons
Loss of transparency or incorrect sizing

Common pitfalls include:

Not resizing images to favicon-friendly dimensions
Losing transparency when converting incorrectly
Failing to include multiple sizes within the ICO file

Proper conversion ensures that your favicon isn’t just visible—it’s clear, sharp, and appropriately scaled for every browser and device. So don’t skip the conversion step; it’s non-negotiable for a professional web presence.

II. Strategic Reasons to Convert WebP to ICO

A. Browser Compatibility Essentials

When it comes to web development, one of the cardinal rules is: don’t assume all browsers behave the same. Sure, many modern browsers like Chrome and Firefox support newer image formats like WebP for content images. But favicons? That’s a whole different ballgame.

Favicons must work everywhere—from Chrome to Safari to old versions of Internet Explorer. And believe it or not, several browsers still rely on ICO files for favicon rendering. These include:

Internet Explorer (all versions)
Microsoft Edge (older versions)
Safari on macOS (limited support for non-ICO favicons)
Some legacy mobile browsers and embedded web views

That means if you’re relying on WebP alone for your favicon, you’re effectively leaving part of your audience in the dark. Your site might show up beautifully on one platform, but completely blank on another. That kind of inconsistency damages user trust and brand continuity.

By converting your WebP image into an ICO file, you ensure your favicon appears exactly how you intended, regardless of browser quirks. It’s the glue that holds your visual branding together across diverse digital environments.

Let’s not forget another critical factor: Windows desktop applications and Progressive Web Apps (PWAs). These often rely on ICO files for app icons, especially in environments where the browser and operating system interact directly.

In short, converting WebP to ICO isn’t just a matter of preference—it’s a smart, strategic move to protect your brand consistency across the internet’s vast browser ecosystem.

B. SEO and UX Considerations

Here’s a little-known fact: favicons can influence your website’s search engine presence. They don’t directly impact rankings in the way content or backlinks do. Still, they play a critical role in user experience, and UX is a ranking factor.

Let’s break it down:

Search Snippets: Google sometimes shows favicons next to site titles in mobile search results. If your favicon isn’t loading correctly, it might not appear, making your result less visually appealing.
Bookmarks and Tabs: When users bookmark your site or pin it to their home screen, the favicon becomes your icon. If it’s missing or looks bad, users may be less inclined to revisit.
Bounce Rate: First impressions matter. A professional, consistent favicon can increase trust and reduce bounce rates. Users are more likely to stay on a site that looks legitimate.

From a technical standpoint, ICO files are also optimized for performance in this context. Since they contain multiple resolutions, browsers can load the most miniature version suitable for the environment, reducing load time and increasing efficiency. That’s not something a single-resolution WebP file can do.

Additionally, having a valid ICO favicon can reduce 404 errors in your server logs. Many browsers automatically request /favicon.ico even if it’s not explicitly referenced in your HTML. If it’s missing, it results in unnecessary 404 requests—something Google doesn’t like to see when crawling your site.

Bottom line: an ICO favicon isn’t just about looks. It’s about keeping your SEO tight, your UX seamless, and your brand recognizable at every touchpoint.

Creating Multi-Size ICO Files for High-DPI Devices

When creating your ICO file, include:

16x16 (tab icon)
32x32 (desktop browser)
48x48 (Windows Explorer)
64x64 or 128x128 (Retina and HD screens)

This guarantees perfect scaling and sharpness on all displays.

WebP to ICO: A Small Change, A Big Impact

Converting WebP to ICO may feel like a technicality. Still, it’s a game-changer for cross-browser consistency, brand recognition, and user experience. WebP is fantastic for modern image optimization, but ICO remains king in favicon land.

Taking the time to prepare a clean, multi-resolution ICO ensures your site looks polished on every browser and every device, from dusty old desktops to shiny new smartphones.

And let’s face it—on the modern web, every pixel counts.