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PNG to ICO Converter

PNG is lossless and supports transparency, but files are often far larger than needed. Converting to Windows ICO icons gives you the icon format browsers look for at /favicon.ico and Windows uses for shortcuts. Lossless compression works by finding repetition, and photographs have very little. A photo saved as PNG is routinely five to ten times the size of the same photo as a good-quality JPEG with no visible difference — which is the single most common cause of a slow-loading page. Website favicons and Windows shortcut icons — a square source with clear shapes that still read at 16 pixels. Drop your files below and the work happens on your own machine: the conversion runs in the browser through the Canvas API, so nothing is uploaded, there is no file-size cap, no watermark and no sign-up. Batches are fine — drop a folder's worth and take them back as a single ZIP.

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or click to browse — JPG, PNG, WebP, HEIC, AVIF, GIF, BMP, SVG

Private: files never leave your device

What a PNG file actually is

PNG arrived in 1996 as a patent-free replacement for GIF and compresses with DEFLATE — the same algorithm as ZIP. Nothing is discarded, so a PNG decodes to exactly the pixels that went in, and it carries a full 8-bit alpha channel rather than GIF's single transparent colour.

Screenshots on every operating system default to PNG, as do exports from design tools and most logo and icon assets. Anything with crisp edges, flat colour or a transparent background has probably been living as a PNG.

What you get from ICO

ICO is a container that holds one or more small square images, with transparency, for use as an icon. It caps out at 256×256 — anything larger has to be scaled down, and the format is not intended for general pictures.

Every browser requests /favicon.ico by default, with no HTML required, and Windows uses ICO for application and shortcut icons. It is a narrow format that is completely reliable inside its niche.

What changes when you convert PNG to ICO

Both formats are lossless, so nothing is thrown away in either direction — this is a container change rather than a quality decision. What differs is how efficiently each one packs the same pixels, and how widely each is supported by the software you need to open it in.

Transparency survives intact. Both PNG and ICO carry a full 8-bit alpha channel, so cut-outs, drop shadows and anti-aliased edges convert without a white box appearing behind them, and the result still composites cleanly onto any background colour.

ICO cannot exceed 256×256, so anything larger is scaled down to fit while keeping its aspect ratio. Work from a square source if you can — a wide image gets letterboxed into the square, and fine detail disappears entirely at the 16-pixel size a browser tab actually renders.

PNG is the usual favicon source and needs no preparation beyond being square. Because both formats are lossless, the icon is exactly the design you drew, right down to the transparent corners of a rounded badge.

Frequently asked questions

Is this PNG to ICO converter really free and private?

Yes. Conversion happens entirely in your browser using the Canvas API — your PNG graphics are never uploaded to a server, there is no file limit, no watermark and no sign-up.

Can I convert multiple PNG files at once?

Yes — drop any number of files and they convert in one batch. Use "Download all" to save the results as a single ZIP.

What size will my ICO file be?

ICO cannot store an image larger than 256×256, so anything bigger is scaled down to fit while keeping its aspect ratio. For a browser favicon a square source works best — 256×256 covers every modern use, and browsers scale it down to the 16 or 32 pixel tab icon themselves.

How do I use this as my website favicon?

Save the file as favicon.ico in your site's root directory. Browsers request /favicon.ico automatically, so no HTML is strictly needed — though adding <link rel="icon" href="/favicon.ico"> makes it explicit.

Does converting PNG to ICO lose quality?

Both formats are lossless, so nothing is thrown away in either direction — this is a container change rather than a quality decision. What differs is how efficiently each one packs the same pixels, and how widely each is supported by the software you need to open it in.

Should the icon be square?

Yes. ICO holds square images, so a wide or tall source is fitted into the square and ends up with empty space around it. Start from a square design with generous margins — the tab icon renders at 16 pixels, where anything intricate turns to mush.

Is it worth converting my screenshots away from PNG?

Usually not. Screenshots are exactly what PNG is good at — flat colour, sharp text, few gradients — so they compress well losslessly and JPEG would smear the text. Convert photographs out of PNG, not interface captures.

Related conversions

JPG → ICOPNG → JPGPNG → WebPWebP → ICOHEIC → ICOAVIF → ICO

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