An app icon is the small, high-contrast emblem users tap on a phone home screen, recognize in a store listing, or spot inside a desktop dock. Unlike a single marketing logo file, shipping software today means delivering dozens of raster sizes: each platform scales artwork for notifications, settings rows, splash templates, store marketing tiles, and adaptive launcher masks. SynthQuery’s App Icon Generator is a free, browser-based utility that respects that reality. You upload one sharp master—ideally a 1024×1024 PNG with transparency where appropriate—pick whether you need every platform or only iOS, Android, Windows, or macOS, optionally preview how your artwork looks under an iOS-style rounded rectangle mask or a circular crop reminiscent of Android adaptive icon foregrounds, and export every requested dimension as a lossless PNG gathered into a ZIP with one folder per ecosystem. Decoding, resampling, clipping, encoding, and archiving all happen locally through HTML5 Canvas and a dynamic JSZip import, so your unreleased brand marks and beta UI never need to traverse a third-party icon batching service just to resize pixels. When the same launch includes AI-assisted release notes or help center copy, continue to SynthQuery’s AI Detector and Humanizer so textual claims stay aligned with your authenticity policies, and bookmark the free tools hub plus https://synthquery.com/tools for the wider catalog of lightweight editors beside the core AI suite.

SynthQuery maps each platform toggle to an explicit list of pixel widths and heights (all square) drawn from commonly referenced submission grids: iOS includes notification, settings, spotlight, and springboard densities through the 1024 marketing asset; Android covers 48 through 512 for launcher and Play feature art workflows; Windows spans 44 through 310 for Start menu and Microsoft Store tile contexts; macOS lists 16 through 1024 suitable for Xcode icon sets and Retina desktop targets. The “All platforms” preset batches every size in one pass; single-platform modes trim the job when you are only refreshing a Windows MSIX or patching an Android-only hotfix. Shape controls stay intentionally simple: “Square” performs a center-weighted cover crop so your artwork always fills the canvas without letterboxing, “Rounded corners (iOS-style)” clips to a continuous corner radius proportional to the edge length—an approximation of the squircle language iOS users recognize, though Apple’s true mask is a superellipse curve the OS may still reapply at runtime—and “Circular crop (Android-style)” inscribes a circle inside the square, helpful when you want flattened previews that resemble adaptive icon foreground discs. The preview grid groups results under headings for iOS, Android, Windows, and macOS so art directors can scan for outliers before handing files to engineering. Image smoothing uses the browser’s high-quality interpolation path during drawImage scaling, which favors stable luminance when shrinking detailed logos. Export format is PNG throughout to preserve alpha when your master includes transparency; opaque masters still benefit from PNG’s lossless edges around typography. ZIP packaging mirrors other SynthQuery imaging utilities: folders, not a flat dump of ambiguous names, so CI jobs can unzip straight into platform-specific resource trees with minimal renaming.

Canvas resampling uses drawImage from your decoded master into each square target with imageSmoothingQuality set to high, which tells the browser to favor a better downscaling filter than nearest-neighbor. Cover math computes the uniform scale that fills the destination and centers the crop, equivalent to CSS object-fit: cover on a square box—logo designers should keep padding inside the master because extreme aspect ratios will lose edge content. The iOS-style mask applies a rounded rectangle clip whose corner radius is a fixed fraction of the edge length; this approximates the visual weight of Apple’s icon silhouette for preview purposes but is not a bitwise match to the official superellipse mask, which uses a different parametric curve and may still be composited by SpringBoard on top of your PNG. Android adaptive icons separate foreground and background layers in actual projects; the circular mode here is a raster shorthand for “disc-shaped artwork” reviews, not a replacement for vector XML adaptive definitions. Windows Store tile manifests historically mix square and wide assets; the sizes included here align with frequent square tile requests. macOS .icns files are containers; designers often assemble them in Xcode from PNG sources—this tool supplies those PNG stairs. ICO files for legacy desktop shortcuts are a different container (see SynthQuery’s PNG-to-ICO tool) and are not bundled in the default ZIP because mobile-first pipelines rarely need them in the same archive. Transparency is preserved whenever the browser’s PNG encoder honors alpha in the drawn region outside masks; masked modes clear pixels exterior to the clip so backgrounds stay transparent in viewers that support it.

Indie developers shipping their first TestFlight build use the generator to avoid maintaining a spreadsheet of pixel triples. Agencies bundle ZIP exports with brand guidelines so client engineering teams drop files straight into Android mipmap buckets and Xcode image sets. PWA authors who also publish native wrappers reuse the same master for manifest icons and notification badges. Electron maintainers pair Windows tile sizes with macOS dock icons without opening a second vendor-specific web app. Game studios generating seasonal app marks batch variants after art swaps. Enterprise mobility groups auditing icon compliance across white-label apps export only the platform they are certifying that week. Cross-platform Flutter or React Native shops treat the ZIP as an intermediate artifact between design sign-off and pipeline commits. Educators teaching mobile HCI can demonstrate density independence with tangible file names instead of abstract @2x vocabulary alone.

Follow this sequence when you need a reproducible icon pack from a single approved master.