What's the difference between PNG and ICO?

PNG is a lossless raster format that supports transparency. ICO is the Windows icon format and the classic home of the site favicon.ico.

Why convert away from PNG?

PNG is a lossless raster format that supports transparency. Where it falls down: photographs and large naturalistic images (file size is huge); anywhere bandwidth or page-weight matters (use WebP or AVIF instead). ICO addresses that for most workflows.

When is ICO the right format?

ICO is a good choice for: site favicons (favicon.ico) and Windows application/shortcut icons; bundling several icon sizes in one file. It is a poor choice when photographs and general web images (use WebP, JPG, or PNG).

Anything surprising about PNG or ICO?

PNG-8 uses a palette of up to 256 colors and is much smaller than PNG-24, but loses gradient fidelity. And on the ICO side: modern .ico files embed PNG frames; convert.now packs a single PNG frame per icon.

Does this work on mobile?

Yes. The drop zone falls back to your phone's file picker, and conversions run on-device just like desktop. Large files may be slower on mobile due to CPU and memory constraints, but the workflow is identical.

What's the maximum file size?

No hard limit — the browser handles it. Files under 50MB convert in a few seconds. Larger files work but may take longer as the browser allocates memory. If you hit issues, batch in smaller groups.

Convert PNG to ICO

Turn a PNG into a multi-resolution ICO favicon. PNG's transparency is preserved. Free, in your browser.

Drop images to convert

PNG, JPG, WebP, AVIF, JPEG XL, TIFF, BMP, GIF, SVG, HDR, ICO — any combination

Files stay on your device. Open DevTools' Network tab to verify.

Output format

ICO

Overview

Why convert PNG to ICO

ICO is a more practical choice than PNG for most modern workflows: site favicons (favicon.ico) and Windows application/shortcut icons. Coming from PNG, the thing to know is that photographs and large naturalistic images (file size is huge).

Comparison

PNG vs ICO: what actually differs

PNG compared with ICO across encoding, fidelity, file size and support.
Attribute	PNG	ICO
Compression	Lossless	Lossless
Transparency	Yes	Yes
Animation	No	No
Typical file size	Very large	Varies
Browser support	Universally supported in every browser since the late 1990s.	Universally supported as a favicon — every browser reads .ico. Not used for general on-page images.

How to

How to convert PNG to ICO

01
Drop your PNG files
Drag one or more PNG files onto the dropzone above, or click to browse. Files stay on your device — nothing uploads.
02
Convert in your browser
convert.now decodes each PNG and re-encodes it as ICO via WebAssembly. The conversion runs in a Web Worker so the page stays responsive.
03
Download the result
Download a single ICO file or, for batch conversions, a zip of all converted files. Filenames preserve the originals.

Why here

Why convert.now

Private
Files stay in your browser. No upload step. Nothing for anyone to see.
Fast
No queue, no upload wait. Conversion starts the moment you drop a file.
Free
No ads. No file-count limit. No sign-up wall. Just the converter.

FAQ

PNG to ICO: common questions

No. The conversion from PNG to ICO runs entirely in your browser using WebAssembly. Files never leave your device. Open DevTools' Network tab if you'd like to verify — there are no network requests with file contents.

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Last updated 27 August 2026

Why convert PNG to ICO

PNG vs ICO: what actually differs

How to convert PNG to ICO

Drop your PNG files

Convert in your browser

Download the result

Why convert.now

PNG to ICO: common questions

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