Image to ICO

What is an image to ICO converter?

An image to ICO converter takes any source image — PNG, JPG, WebP, AVIF, SVG, GIF, BMP, or any other browser-supported raster or vector format — and re-encodes it into an .ico favicon container. The .ico format is the historical icon format introduced by Microsoft in 1985 for Windows 1.0, and it remains the most universally recognised favicon container across every browser, bookmarking tool, RSS reader, and desktop shortcut generator. By accepting any source format, a general image to ICO converter saves you from running a separate conversion for each format you happen to have on hand.

Internally, this tool loads your source image via the browser's native image decoder (or via a data URL for SVG files), draws it onto a square canvas at the size you choose, fills the background with white, centres the image while preserving its aspect ratio, and then wraps the resulting PNG bytes inside a single-image .ico container. The output is a real favicon.ico file that you can drop into the root of your website or into your project's assets folder.

What is ICO?

ICO is the historical icon container format introduced by Microsoft in 1985 for the Windows 1.0 operating system. An .ico file is not a single image format — it is a small container that can hold one or more bitmaps or PNG-compressed images at different sizes (typically 16×16, 32×32, 48×48, 64×64, 128×128, and 256×256) and color depths. Browsers, the Windows shell, bookmark managers, and desktop shortcuts all look for an .ico file (commonly favicon.ico) at the root of a website to display the site's icon in tabs, history lists, the address bar, and the desktop.

Although modern browsers can also use PNG, SVG, and WebP favicons via the <link rel="icon"> tag, the .ico format remains the most universally recognised favicon container. Older browsers and many third-party tools (bookmark managers, feed readers, RSS clients, desktop link generators) still request /favicon.ico by default, so placing a real .ico file at that URL is the safest way to guarantee every visitor sees your icon. This tool produces a single-size .ico file containing a PNG-compressed image at the size you choose.

Supported source formats

This tool accepts any image format your browser can decode. The table below lists the most common source formats and how they are handled during conversion to ICO.

Source format	Year	Handling
PNG	1996	Decoded natively, drawn to canvas, embedded as PNG inside .ico
JPG / JPEG	1992	Decoded natively, drawn to canvas, embedded as PNG inside .ico
WebP	2010	Decoded natively in modern browsers, embedded as PNG inside .ico
AVIF	2019	Decoded in modern browsers (Chrome 85+, Firefox 93+, Safari 16+), embedded as PNG inside .ico
SVG	2001	Loaded as data URL via FileReader, rasterized to canvas, embedded as PNG inside .ico
GIF	1987	First frame decoded natively, drawn to canvas, embedded as PNG inside .ico
BMP	1985	Decoded natively, drawn to canvas, embedded as PNG inside .ico

Whatever source format you start from, the output is always a real .ico container holding a PNG-compressed image at the size you choose. SVG files are loaded through a FileReader-based data URL pipeline so that external references are inlined and the SVG can be rasterized reliably.

When to use Image to ICO conversion

There are many real-world situations where converting an image to an .ico favicon is the right move. Whenever a platform, service, or workflow expects a real .ico file rather than a modern image format, a single image to ICO conversion gives you a universally recognised favicon:

• Launching a new website. Placing a real favicon.ico at the site root ensures every browser — including older ones that ignore <link rel="icon"> tags — shows your icon in the tab.
• Legacy tool compatibility. Bookmark managers, RSS readers, and desktop link generators still request /favicon.ico directly. A PNG or SVG cannot satisfy that request, but an .ico file can.
• Desktop shortcuts. When a user drags a URL to the desktop, Windows and many Linux file managers pull the icon from favicon.ico, so a real .ico file is required for a crisp shortcut.
• Progressive Web Apps. A PWA's manifest.json can reference .ico files for legacy install contexts and older Android and Windows shell integration.
• Windows application icons. Many Windows development tools still expect an .ico file when assigning the application icon to a compiled executable.
• Brand consistency. Distributing a single .ico file across web, desktop, and bookmark channels keeps your icon identical everywhere, regardless of the source format your design team used.

Keep your source image as the editable master — it can be re-exported at any resolution. Use the .ico export when you need a compact, fixed-size favicon for deployment scenarios where ICO is still the expected format.

How to convert an image to ICO

Converting any image to an .ico favicon with this tool takes only a few seconds and happens entirely inside your browser. No upload, no sign-up, and no installation are required. The tool detects whether your file is an SVG (and loads it via a data URL for reliable rasterization) or any other raster format (and loads it via the browser's native image decoder), draws it onto a square canvas at the size you choose (preserving aspect ratio and centring on a white background), and then re-encodes the canvas into an .ico container via the Canvas API. Follow these four steps:

1. Upload your image. Click the upload area or drag and drop a .png, .jpg, .webp, .avif, .svg, .gif, or .bmp file from your computer. The image is decoded locally and shown as a preview.
2. Choose the ICO size. Pick one of 16, 32, 48, 64, 128 or 256 px. 32×32 is the standard favicon size; 16×16 is the classic tab icon; 48×48 and larger are used by high-DPI displays and desktop shortcuts.
3. Convert to ICO. Click the "Convert to ICO" button. The tool draws your image onto a square canvas at the chosen size and wraps the PNG bytes inside a single-image .ico container, showing the original and converted file sizes side by side.
4. Download the ICO. Click "Download ICO" to save favicon.ico to your device. Upload it to the root of your website or drop it into your project's assets folder.

Because every step runs locally in your browser using JavaScript, your image is never uploaded to a server. This makes the conversion completely private, fast, and suitable for sensitive brand assets.