About Icon Checker
What Icon Checker is, how the checks work, and which official rules they follow.
Maintained by Icon Checker
What problem does Icon Checker solve?
App icon and favicon requirements are easy to confuse because the files look similar while their submission rules differ. A Google Play listing icon is not an Android adaptive icon; an iOS Primary icon does not share every rule with Dark and Tinted variants.
Icon Checker keeps those contexts separate. It measures facts such as a 1024 x 1024 iOS source canvas, a 512 x 512 Google Play listing asset, exact PNG bytes, alpha metadata, decoded transparency, and website icon declarations. Every result shows the observed value, the expected value, and the source behind the rule.
How are checks classified?
- Deterministic: dimensions, file bytes, PNG mode, alpha metadata, and decode success.
- Warning: evidence is incomplete, such as an untagged source color profile.
- Manual: visual balance, baked-in masks, platform shadows, and small-size legibility.
What stays private?
App icon analysis runs in the browser. The selected PNG is not sent to an App Icon audit API, saved to a report database, or assigned a public result URL. The favicon checker uses an isolated, constrained fetch service for public website resources and rejects private networks, unsafe ports, oversized responses, redirect loops, and expired deadlines.
Which official sources define the rules?
Hard rules are mapped to documentation published by the platform owner. The current source set includes the following primary references:
- Apple Human Interface Guidelines: App icons
- Google Play Console: Add preview assets
- Android Developers: Google Play icon design specifications
- Google Search Central: Define a favicon
Each automated result carries a stable rule ID, rule version, and review date. These checks catch known technical mismatches; they do not guarantee browser display, search appearance, App Store approval, or Google Play approval.
Who maintains Icon Checker?
Icon Checker maintains the checker implementation and rule mappings. Corrections should cite an official platform document and the affected rule ID so the evidence can be reproduced. Send a correction or checker bug to hello@iconchecker.com, or review the requested details on the Contact page.