Resize an ICO file, remove the sizes you don't need, or swap in your own artwork for any size - all in your browser. Starting from a PNG, JPG or SVG works too; for a website icon set, try the Favicon Resizer.
Drop your ICO or image hereor click to browse - or paste with Ctrl+VICOPNGJPGSVGWebPGIFBMPAVIF
Have hand-drawn small sizes? Drop them together with your big image - each one fills the size that matches it.
Runs in your browser - nothing is uploaded
Recent icons in this browser
icon.ico
Icon sizes
0 selected
In file Added Use your own image Removed / not included
Open your icon. Drop an ICO file - or a PNG, JPG, WebP, SVG or other image - onto the box, paste it, or click to browse. It stays on your device.
Choose the sizes. Sizes already in your file are marked In file. Click tiles to add or remove sizes, use a preset, or add a custom size. Drop your own image on a tile to replace that size.
Check the preview. Each size is shown at actual size and zoomed, plus how it looks in a browser tab, on the taskbar and on the desktop.
Pick the output. Keep one ICO with every size inside, or get separate PNG or ICO files in a ZIP archive.
Resize and download. Click Resize icon, compare the before and after, and download the result.
Which icon sizes do you need?
It depends on where the icon will be shown.
An ICO file can hold many sizes, and Windows or the browser picks the one that fits the screen.
Use
Sizes to include
Where it shows
Website favicon
16, 32, 48
Browser tabs, bookmarks, history, Windows site shortcuts
Windows app or shortcut
16, 20, 24, 32, 40, 48, 64, 256
Explorer, taskbar, Start menu and desktop at 100% to 250% display scaling
File-type icon
16, 32, 48, 256
Explorer lists, details view and large icon views
Toolbar or tray icon
16, 20, 24, 32
Notification area and small toolbar buttons
The in-between sizes matter on modern screens. A 16 px icon is drawn at 20 px on a display set to 125%, at 24 px at 150% and at 32 px at 200%.
If the exact size is missing, Windows shrinks the next larger one, which is where soft, blurry icons come from. The Windows app preset adds all of them in one click.
Phones and apps use separate PNG files rather than ICO. For an Apple touch icon, Android icons and the web manifest, use the Favicon Package Generator.
Keep small sizes sharp
Shrinking is safe; enlarging is not.
Every new size is made from the largest image in your file, scaled down in halving steps so thin lines survive at 16 and 24 px. The preview panel shows each size zoomed, so you can spot a muddy detail before downloading.
If the tool warns that a size is larger than your source, start from a bigger image. You can enlarge a small PNG with the Image Upscaler, or build the icon from a vector with SVG to ICO.
Use your own artwork for small sizes
Designers often draw 16 and 32 px icons by hand.
A scaled-down logo loses thin lines at those sizes, while a pixel-drawn version stays crisp. Click the image button on a tile, or drop a PNG onto it, and that size uses your file pixel for pixel.
To build a whole icon from separate files, drop them all at once. The largest image becomes the source, and each smaller one fills the size that matches its dimensions - for example icon-16.png goes into 16 x 16. Check the result in the ICO to PNG converter, which shows every size inside.
Classic and modern ICO files
ICO files come in two flavours.
Older icons store each size as a bitmap (BMP), sometimes with only 16 or 256 colours. Newer ones use compressed PNG images, usually for the 256 px size. This tool reads both, including icons with an 8-bit palette and a separate transparency mask.
The file it writes uses the layout Windows handles best: 32-bit bitmaps with a transparency mask below 256 px, and a 32-bit PNG at 256 px. That works in every Windows version, in Explorer and Photos, and in all browsers. For very old programs you can switch the colour depth to 24 or 8-bit.
To see exactly what is inside an icon, open it in the ICO Analyzer. To make a large icon smaller on disk, use Compress ICO, and to pull the icon out of a program, use the EXE Icon Extractor.
Icon Resizer or Favicon Resizer?
Use the Icon Resizer to edit an icon you already have: see which sizes are inside, remove the ones you don't need, add the missing ones and replace any size with your own drawing.
Use the Favicon Resizer when you are starting from a logo and need the standard set of website icon files. To create an icon from scratch, try the Icon Maker, or convert a JPG to ICO or WebP to ICO.
Frequently Asked Questions
Upload the ICO file above. Every size inside it is shown as a tile - click a tile to remove it, click an empty size to add it, or pick a preset such as Favicon or Windows app. Then click Resize icon and download the new file.
Yes. Sizes that are already in your file are marked In file. Click one to mark it Remove and it is left out of the new ICO. The sizes you keep are copied pixel for pixel, not resampled.
Each image inside an ICO file can be at most 256 x 256 pixels - the format has no way to record a larger size. If you need 512 x 512, choose PNG output instead, or convert the result with ICO to PNG.
Yes. Upload a PNG, JPG, WebP, GIF, BMP, AVIF or SVG image, choose the sizes you want and keep the output on ICO. Transparency is kept, and non-square images are centred on a transparent square instead of being stretched. For a vector logo, SVG to ICO gives the sharpest small sizes.
Usually because a size was made larger than the source. A 32 x 32 image stretched to 256 x 256 has to invent pixels. Start from the largest image you have, or enlarge it first with the Image Upscaler. Include every size Windows asks for, so it never has to shrink a big frame on the fly.
Yes. Click the small image button on any size tile, or drop a PNG onto the tile, and that size uses your artwork instead of a scaled copy. You can also drop several images at once: the largest becomes the source and every other image fills the size that matches its own dimensions, so hand-drawn 16 and 32 px versions end up in one ICO. Need a brand-new design instead? The Icon Maker adds shapes, padding and backgrounds.
Yes. Transparent areas stay transparent in every size. Sizes below 256 px are saved as 32-bit bitmaps with a transparency mask and 256 px as a 32-bit PNG, which is the layout Windows reads most reliably.
Yes. The Icon Resizer runs in your browser, so your icon is never uploaded. Only an icon your browser cannot read is sent to our server once to decode it, and it is deleted straight away. No account is needed.
