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PNG to ICO

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Turn a PNG logo into a favicon.ico or a Windows icon, transparency included.

or paste with CtrlV JPG, PNG, WebP, AVIF, GIF or BMP

Your files never leave your device

About this tool

PNG to ICO converter for favicons and Windows icons

Convert a PNG to ICO for a favicon.ico or a Windows icon that holds 16, 32, 48 and 256 px in one file, as far as your image allows. Transparency is kept, and a logo that isn’t square is centred on a clear background, never cropped. Our 512 px test logo became a 30.4 KB icon.

What a favicon needs from your PNG

An ICO holds several square sizes in one file, and each place that shows your icon picks the closest: a browser tab, a bookmark, a search result, a Windows shortcut. ToolHero writes 16, 32, 48 and 256 px, the sizes Windows Vista and 7 shipped with. Google Search asks for a square favicon of at least 8 px and recommends more than 48.

Start from the biggest, sharpest PNG you have. Every size is scaled down from your image, never from another icon size. Sizes bigger than your PNG are left out rather than blown up, except 16 and 32, which a small logo is enlarged to, at most twice its size.

Transparent edges at 16 pixels

Your PNG’s alpha channel carries over into every size, soft edges included, so the icon sits cleanly on a light tab and a dark one. The resizing works on premultiplied colour, which keeps dark fringes from creeping in around the shape.

Detail is the hard part. A 512 px logo shrinks 32 times to make the 16 px icon, so hairlines and small lettering vanish. Logos built from one bold shape survive best; if yours has a wordmark, try the symbol on its own.

Putting favicon.ico on your site

Name the file favicon.ico and put it in the top folder of your site. Browsers have looked for it there since Internet Explorer 5 in 1999, and all of them still do. To say so explicitly, add one line to the head of your pages:

In the <head> of your HTML
<link rel="icon" href="/favicon.ico">

Why convert PNG to ICO?

  • What you gain

    One .ico file holds every size a browser tab, a bookmark or a Windows shortcut needs, and a PNG with a transparent background makes the cleanest icon of all.

  • Good to know

    Thin lines and small lettering disappear at 16 px. A bold, simple mark reads best, so try the symbol without the wordmark if the small sizes look busy.

  • Measured on our test logo

    Our 512×512 logo on a transparent background, a 14,208-byte PNG, became a 30,403-byte ICO holding 16, 32, 48 and 256 px: 2.14× the size, because it stores four pictures. The 256 px one is a 15,301-byte PNG, and the three small ones are 32-bit bitmaps, the form every Windows since XP reads, 15,032 bytes together. Every edge stayed see-through. Our 1800×750 signature, a wide 166,863-byte PNG, became a 25,681-byte ICO (0.154×), centred on a clear square.

    Tested with ToolHero’s ICO writer, Lanczos3 resizing from @jsquash/resize 2.1.1 and oxipng 9.1.1 (@jsquash/oxipng 2.3.0) writing the 256 px PNG on a Mac18,5 (Apple M6) on macOS 27.0.1, 2026-10-14. The output was byte-identical in Chromium, Firefox and WebKit.

How it works

  1. Add your PNG

    Drop in a logo or an icon, ideally 256 px or larger, with a transparent background if it has one.

  2. Convert

    ICO is already picked. Press Convert and each PNG becomes one icon holding every size it allows.

  3. Save it as favicon.ico

    Download the icon. For a website, name it favicon.ico and put it in the site’s top folder.

PNG vs ICO at a glance

How the two formats compare, so you know what to expect.

  • PNG

    Your files

    A lossless format that keeps every pixel exactly. Great for screenshots, logos and anything with text or sharp edges.

    Best for Screenshots, logos, diagrams, cut-outs with transparency, and master copies you will edit again.

  • ICO

    What you get

    A small file of square pictures at several sizes, so Windows and browsers can show the sharpest one wherever the icon appears.

    Best for Website favicons, and the icons of Windows programs and shortcuts.

PNGICO
CompressionLosslessLossless (bitmaps and PNG)
TransparencyYesYes
AnimationRarely (APNG)No
Photo file sizeOften 3–5× a JPGSmall: 256 px at most
Opens inEverywhereEvery major browser and Windows

Questions, answered

Which sizes end up in my favicon.ico?

Up to four: 16, 32, 48 and 256 px. Sizes larger than your PNG’s longer side are left out. 16 and 32 are the exception: a smaller logo is enlarged to reach them, but never past twice its size. A 512 px logo gets all four.

Does the see-through background survive?

Yes. Every size keeps your PNG’s alpha channel, soft edges included, and the space added around a logo that isn’t square is transparent too.

My logo is wider than it is tall. Will it be cropped?

No. It’s scaled to fit the square and centred, with clear space above and below. To fill the square instead, crop the PNG to 1:1 before converting.

Do I still need a favicon.ico if my site links PNG icons?

Modern browsers use the icons you link. A favicon.ico in your site’s top folder still works everywhere without any link, which makes it a safe fallback.

How small can my PNG be?

8 px on its longer side, which is enough for a 16 px icon. That is also the minimum Google Search accepts, though it recommends more than 48 px.

Is my logo sent anywhere to be turned into an icon?

No. Your browser resizes the PNG and packs the icon itself, on your device. Nothing is sent to a server.

Related conversions

Everything happens on your device, so your files never leave your computer or phone.

Favicons and Windows icons.To ICO · 16–256 px

To ICO · 16–256 px
PNG to ICO settings

Convert to

Icon sizes

16, 32, 48 and 256 px as far as each image allows, padded to a square, never cropped.

Add images to convert them