PNG to ICNS Converter
Build a macOS .icns icon from a square PNG without opening Xcode or Terminal. Use it for a script bundled as an app, a disk image, a folder or an Electron build, and see below how the full iconset works when you ship through Xcode.
Image Converter
or drop JPG, JPEG, JPE … files here ·
Max 95 MB per file· Up to 20 files· Deleted after 30 minutes
Files are processed on our servers and deleted after 30 minutes.
85 keeps photos visually identical to the original. Lower it only when you need a smaller file.
JPG, BMP and EPS have no transparency. Transparent pixels are filled with this color.
Hex color used behind transparent pixels, e.g. #FFFFFF.
This format holds a single image. Choose GIF or WebP output if you want to keep the animation.
A multi-size icon contains several resolutions in one file; browsers and operating systems pick the one they need.
Keep the original dimensions, or enter one side and the aspect ratio is kept.
Pixels for the side you chose above.
Percentage of the original dimensions.
sRGB is right for screens and the web. Keep the original for print workflows; grayscale discards color.
Metadata only, 0 keeps the original value. Printers and some portals read this number; it does not change pixel dimensions.
How to use this tool
- 1
Upload a square PNG
Use transparent artwork of at least 1024 × 1024 px.
- 2
Keep every size
Under Advanced settings, Icon sizes is set to All sizes (16–256), so Finder lists, sidebars and Dock tiles each get a matching image.
- 3
Convert to ICNS
Press Convert to ICNS and download the .icns file, ready for an app bundle's Resources folder or a Get Info window.
An .icns file is Apple's icon container: one file, many square bitmaps, each drawn by Finder, the Dock or Spotlight at the size it needs. Converting a PNG fills those slots from one piece of artwork.
PNG to ICNS: what a macOS icon file contains
Apple introduced the ICNS format with Mac OS 8.5 in 1998, and Mac OS X kept it as the file every application bundle points to. The container has grown with screen density: 512 px entries arrived with Mac OS X 10.5, and the 1024 px entry, labeled 512 × 512 @2x, came with Retina displays in OS X 10.7 and 10.8.
Each slot is a pair: a 1x image and an @2x image of the same point size for Retina screens. Finder picks the one that matches the display and the view, which is why a single 1024 px PNG scaled down by Finder looks blurrier in list view than a real 16 px entry does.
Mac iconset sizes from 16 px to 1024 px
| Point size | 1x file (pixels) | @2x file (pixels) | Seen in |
|---|---|---|---|
| 16 pt | icon_16x16.png (16) | [email protected] (32) | Finder list view, menus |
| 32 pt | icon_32x32.png (32) | [email protected] (64) | Sidebar, small icon view |
| 128 pt | icon_128x128.png (128) | [email protected] (256) | Finder icon view, Dock |
| 256 pt | icon_256x256.png (256) | [email protected] (512) | Large icon view, Quick Look |
| 512 pt | icon_512x512.png (512) | [email protected] (1024) | Get Info preview, App Store |
mkdir MyApp.iconset sips -z 512 512 icon-1024.png --out MyApp.iconset/icon_512x512.png cp icon-1024.png MyApp.iconset/[email protected] # repeat sips for 16, 32, 64, 128 and 256 px files iconutil -c icns MyApp.iconset
PNG
Portable Network Graphics
PNG is a lossless raster format published in 1996 by the PNG Development Group and later standardised by the W3C and ISO. It keeps every pixel exactly, supports full alpha transparency and handles text, sharp edges and flat colours without artefacts. That precision makes it ideal for screenshots, logos, icons and interface graphics. The trade-off is size: photographs saved as PNG are often several times larger than the same photo as JPEG or WebP. All browsers, operating systems and editors open PNG files.
- Compression
- Lossless
- Transparency
- Yes
- Animation
- No
- Introduced
- 1996 · PNG Development Group
ICNS
Apple Icon Image
ICNS is Apple's icon container format, used for application, folder and document icons in macOS since Mac OS 8.5 in 1998. A single file bundles several sizes, from 16×16 up to 1024×1024 pixels, including Retina versions, usually stored as PNG data with transparency. Xcode and macOS read it directly, but it is rarely used outside Apple platforms. Windows and most web tools cannot open ICNS without a converter.
- Compression
- Lossless
- Transparency
- Yes
- Animation
- No
- Introduced
- 1998 · Apple
A PNG becomes ICNS when a Mac app bundle, installer or folder needs Apple's icon container with several resolutions in one file; ICNS goes back to PNG only to reuse an existing app icon in a document or on a website.
Online ICNS converter or Xcode and iconutil
This converter fills the slots from 16 to 256 px, which covers Finder lists, the sidebar, the Dock and icon view on every Mac, Retina included up to the 128 pt slot. That is what a folder icon, a DMG volume icon, an AppleScript or Automator app, or an internal tool needs, with no developer tools installed.
For an app you submit to the Mac App Store, use the 1024 px source in Xcode's asset catalog or run iconutil on a complete iconset as shown above, so the 512 pt slots are filled from real pixels. Start from a clean square: if your logo is wide, the crop image tool gives you a 1:1 canvas first, and how to crop an image to a ratio explains where to leave padding.
PNG to ICNS questions from Mac users
How do I put a custom ICNS icon on a Mac folder or app?
Select the item in Finder, press Command-I to open Get Info, then drag the .icns file onto the small icon at the top-left of the window. For an app you build yourself, place the file in Contents/Resources and name it in the CFBundleIconFile key of Info.plist.
What PNG size should I start from for an ICNS?
1024 × 1024 px, the largest slot Apple defines. A smaller PNG still converts, but every size above the source is upscaled and looks soft on Retina screens. The artwork should be square with a transparent background outside the icon shape.
Do I need a hand-made ICNS if my Xcode project has an asset catalog?
No. When a macOS target uses an AppIcon set in Assets.xcassets, Xcode compiles it and generates the app's icon file during the build. A separate .icns is for projects without Xcode: shell-script apps, Electron and Tauri packagers, Python bundlers and DMG backgrounds.
Why does my new icon sit inside a gray rounded square?
Since macOS 11 Big Sur, Mac app icons follow a rounded-square shape, and macOS 26 Tahoe places icons that do not fill that shape inside a gray tile. Draw the rounded square into the artwork itself, leaving transparent corners, and the system shows it as designed.
Does an ICNS file compress my artwork?
Not in a way you can see. Modern .icns files store their larger images as PNG data inside the container, which is lossless. Only the tiny legacy entries use Apple's own run-length scheme with a separate 8-bit mask, and those are rarely displayed on current Macs.
Can Windows or Linux use the same icon file?
Windows needs ICO, not ICNS; PNG to ICO makes it from the same artwork. Linux desktops read plain PNG or SVG icons from the theme folders, so the original PNG is already what they want.
