PNG to ICO Converter — Create Real Multi-Size Icon Files Instantly
If you have ever tried to set a custom favicon for a website or a taskbar icon for a Windows application, you already know what an ICO file is. What you might not know is how surprisingly difficult it can be to create one properly. Unlike a simple image rename, a genuine ICO file is a structured binary container that holds multiple resolutions of the same icon at once — allowing Windows and web browsers to pick the most appropriate size for each display context automatically. Our free PNG to ICO Converter creates a proper, standards-compliant ICO file from any PNG image, right in your browser, with zero uploads and zero waiting.
What Makes This Tool Different
Most online ICO converters simply rename your PNG file with a .ico extension, which technically works in some situations but fails in others — particularly in older browsers and native Windows applications that read the ICO format strictly. This tool constructs a genuine ICO binary file from scratch using the Canvas API and JavaScript. It reads your PNG, resamples it to each chosen size using proper bicubic-equivalent scaling, and assembles a correctly structured ICO header and directory table before packaging everything into a downloadable binary file. The result is indistinguishable from an ICO file produced by professional desktop software.
How to Use the Tool
- Step 1 — Upload your image: Drag and drop any PNG, JPG, WEBP or GIF image onto the upload area. The original image can be any dimension — the tool will scale it down to each target size.
- Step 2 — Choose your sizes: Select which icon dimensions to include in the ICO file. Use the Favicon Set preset (16, 32, 256) for websites, or the Windows Set (16, 32, 48, 256) for desktop applications. You can also tick any combination manually.
- Step 3 — Set background: Choose transparent (ideal for logos), white or black background fill for sizes that do not support full transparency in all environments.
- Step 4 — Preview and download: Click Convert to ICO and see a live preview of every size. Click Download to save your .ico file.
Key Benefits
- Real ICO format: Properly structured binary file, not a renamed PNG
- Multi-size in one file: Embed up to 6 sizes — browsers and Windows pick the right one automatically
- Transparent support: Preserves PNG alpha channel transparency in your ICO
- No upload, no account: 100% browser-based, completely private
- Works for favicons and apps: Perfect for website favicons, Windows application icons and desktop shortcuts
Is the ICO file generated a real ICO or just a renamed PNG? +
It is a genuine, properly structured ICO binary file — not a renamed PNG. The tool builds the ICO file from scratch in JavaScript, writing a correct ICO header, directory table and image data for each selected size. It will work correctly in all environments that read the ICO format strictly, including Internet Explorer, Windows Explorer, Windows application launchers and all modern browsers.
Which image formats can I upload? +
You can upload PNG, JPG, WEBP and GIF files. PNG is recommended because it supports transparent backgrounds, which are preserved in the resulting ICO file. JPG images have no transparency, so choose White or Black as the background option when converting from JPG. Animated GIFs are flattened to a single frame.
Which sizes should I choose for a website favicon? +
For a website favicon, click the "Favicon Set" preset which selects 16x16, 32x32 and 256x256. The 16px size appears in browser tabs, 32px is used in some high-DPI displays and system taskbars, and 256px ensures sharp rendering on high-resolution monitors. Modern browsers also support PNG favicons directly, but an ICO with these three sizes gives the widest compatibility across all browsers and operating systems.
Will transparency be preserved in my ICO file? +
Yes, if you select Transparent background and upload a PNG with an alpha channel, the transparency is preserved in the ICO output. Each icon size in the ICO file retains the transparent areas from your original PNG. This is essential for favicons placed on coloured backgrounds, as a transparent ICO will show the page background colour through the non-icon areas.
How large should my source PNG be? +
For the best quality result, use a source PNG that is at least 256x256 pixels — the largest size available in the tool. If you are generating a 256x256 icon from a 16x16 source, the upscaled result will look blurry and pixelated. Start with the largest, sharpest version of your image and let the tool scale it down cleanly to smaller sizes.
Is my image uploaded to a server? +
No. Your image never leaves your browser. The entire conversion process — loading the image, scaling it to each size, and building the ICO binary — happens using JavaScript and the HTML5 Canvas API running on your device. No data is transmitted to any server at any point.
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100% Private
Your image never leaves your browser. Zero server uploads, zero data storage.
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6 Icon Sizes
16, 32, 48, 64, 128 and 256px — all embedded in one proper .ico file.
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Transparency
PNG alpha channel preserved — your ICO works on any background colour.
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Instant & Free
Real ICO binary generated in seconds. No account. No watermark. Forever free.