How to convert PNG to .ico online
Converting a PNG to icon file (.ico) is the standard way to create a favicon or Windows icon. This free PNG to icon converter takes any image — PNG, JPG, WebP, SVG — and produces a properly formatted multi-size .ico file. Your image is converted directly in your browser using the Canvas API and UPNG compression. No upload. No signup.
Drop PNG, JPG, or WebP. PNG with transparency gives the cleanest result. JPG works too — enable "Remove solid background" for white-bg JPGs.
Select icon sizes. Standard favicon needs 16×16, 32×32, 48×48. Add 64, 128, 256px for high-DPI displays and Windows shortcuts.
Download .ico file. One click — get a compressed multi-size icon file (60-80% smaller than typical ICO) ready as favicon.ico.
Convert image to icon — any format to .ico
This icon converter handles any image format your browser can decode: PNG, JPG, JPEG, WebP, SVG, GIF, BMP, AVIF. The pipeline is the same for all formats — decode → resize per selected size → encode as compressed PNG → pack into .ico container. The only difference is that JPG and other opaque formats benefit from the "Remove solid background" option to add transparency.
Convert PNG to .ico — what's in the file?
A .ico file is a container that bundles multiple image sizes. Each size is stored as either a BMP (legacy) or PNG (modern) frame. This tool uses PNG-encoded frames, supported by all browsers since IE 11 — smaller files and full transparency support. Each PNG frame is quantized to 256 colors via UPNG.js, reducing a 16+32+48 multi-size icon from ~15 KB down to ~3 KB.
Convert JPG to ICO online
JPG images convert to icon the same way. Since JPG doesn't support transparency, enable the "Remove solid background" option — the tool automatically detects the background color from the corners and removes it using BFS flood fill. For complex backgrounds, use the Solid Background Remover first for manual control.
Best practice: start with at least a 256×256 source image. Downscaling produces sharp icons; upscaling from a small JPG results in blurry favicons.
Convert WebP to ICO online
WebP is Google's modern image format with superior compression and native alpha transparency support — which makes it an excellent source for ICO conversion. Drop your .webp file directly into this tool. The alpha channel from WebP is preserved across all embedded ICO sizes, so you get a clean multi-resolution favicon without any background artifacts.
Unlike server-based WebP-to-ICO converters, this tool decodes WebP directly in your browser using native <img> support (Chrome, Firefox, Edge, Safari 14+) — no upload needed, instant conversion.
What sizes should I include when creating an ICO from PNG?
| Size | Used by | Required |
|---|---|---|
| 16×16 | Browser tab, bookmarks bar | Yes |
| 32×32 | Retina browser tab, Windows taskbar | Yes |
| 48×48 | Windows desktop shortcut | Recommended |
| 64×64 | Windows high-DPI taskbar | Optional |
| 128×128 | macOS/Linux file managers | Optional |
| 256×256 | Windows Vista+ high-res icon view | Optional |
Minimum: 16 + 32 + 48px covers 99% of use cases. Adding 64 and 128 increases file size but ensures crisp display on high-DPI screens.
ICO file format explained
An ICO file is a container that holds one or more images at different resolutions. Each image can be stored as either BMP (legacy) or PNG (modern, smaller). This tool uses PNG-encoded frames — supported by all modern browsers since IE 11. PNG frames support transparency and compress 3-5x better than BMP frames.
The ICO header (6 bytes) declares the number of images. Each image entry (16 bytes) stores dimensions, color depth, data size, and offset. Browser picks the best size for the context — 16px for tabs, 32px for Retina tabs, 48px for Windows shortcuts.
Compressed vs uncompressed ICO
| Uncompressed (BMP) | PNG frames | Quantized PNG | |
|---|---|---|---|
| 16+32+48 ico | ~15 KB | ~8 KB | ~3 KB |
| 16+32+48+128+256 | ~300 KB | ~80 KB | ~25 KB |
| Transparency | Yes | Yes | Yes |
| Browser support | All | IE11+ | IE11+ |
Related tools
Need a complete favicon setup with HTML snippet and manifest? Use the Favicon Generator — generates .ico + PNGs + Apple Touch Icon + manifest code.
Resize icons to many sizes at once? The Icon Resizer has presets for iOS, Android, Web, Social with ZIP export.
Need Android launcher icons? The Android Launcher Icon Generator creates all density buckets + adaptive foreground.
Convert SVG to raster first? The SVG to PNG Converter exports at any resolution.
Compress PNG files? The PNG Compressor reduces size up to 80% using smart quantization.
Convert between formats? The Image Converter handles PNG, JPG, WebP, AVIF, JPEG XL.
Frequently asked questions
How to convert PNG to ICO?
Drop your PNG into this PNG to icon converter, select the sizes you need (16, 32, 48px minimum for favicon), then click Download. The .ico file is generated in your browser using the Canvas API and UPNG compression — no upload, no signup.
How to convert image to icon online?
Any image format works as a source: PNG, JPG, WebP, SVG, GIF, BMP. Drop the file, select which icon sizes to embed (16-256px), and download a multi-size .ico file. Enable "Remove solid background" for opaque JPG sources.
How do I convert JPG to ICO?
Drop your JPG, enable "Remove solid background" if needed (most JPGs have a white background), select sizes, and download. The tool works for any image format — PNG, JPG, SVG, WebP, GIF, BMP.
How do I convert WebP to ICO?
Drop your .webp file directly — it works exactly like PNG. WebP transparency is fully preserved across all embedded ICO sizes. No need to convert WebP to PNG first.
What is an ICO file?
ICO is a container format that bundles multiple icon images at different resolutions into a single file. It is the standard favicon format used by web browsers and Windows applications.
What sizes should my .ico file contain?
16×16 and 32×32 are essential for browser favicons. Add 48×48 for Windows shortcuts. For high-DPI screens, include 64, 128, or 256px. More sizes = larger file but crisper icons on all displays.
Is this ICO converter really free?
Yes, 100% free with no limits. No signup, no watermark, no daily quota, no upload. All processing runs in your browser using the Canvas API and UPNG.js.
How does compression work?
Each size in the ICO file is stored as a PNG image. This tool uses UPNG.js to quantize PNG colors (default 256-color palette, adjustable), reducing file size 60-80% with minimal visual difference at icon sizes.
Are my images uploaded to a server?
No. All processing runs 100% in your browser using Canvas API and JavaScript. Your images never leave your device — unlike most online ICO converters that upload to their servers.
What is the maximum ICO size?
The ICO format supports images up to 256×256 pixels per frame. For larger icons (512px), use PNG files directly — browsers support them via <link rel="icon"> tags in HTML.
Is ICO still needed in 2026?
Yes. While modern browsers support PNG favicons, ICO remains the most compatible format. It is the only format that works in all browsers including legacy IE. Place favicon.ico in your site root for maximum compatibility.
Does it preserve transparency?
Yes. If your source image has an alpha channel (PNG, WebP), the ICO output preserves full transparency for each embedded size. For JPG sources, enable the "Remove solid background" option.