Asset Catalog Tinkerer is a free, open-source Mac utility that lets you open compiled .car (Core Animation Runtime) asset catalog files and inspect or export every image asset packed inside them.
What is Asset Catalog Tinkerer?
Asset Catalog Tinkerer is a native macOS app built specifically for developers and designers who need to see what lives inside Xcode's compiled asset catalogs. When Xcode builds an app, it takes your Assets.xcassets folder and compresses everything into a single binary .car file. That file ships inside every macOS and iOS app bundle, but the format is opaque — you can't just double-click it. Asset Catalog Tinkerer cracks it open and presents every image variant in a clean, browsable grid.
I first reached for this tool when reverse-engineering the icon sets inside a third-party macOS app to understand a design system — something that used to require arcane assetutil invocations and a lot of terminal squinting. The app makes that workflow immediate and visual.
What does Asset Catalog Tinkerer do best?
Its single greatest strength is zero-friction inspection: drag a .car file (or the app bundle itself) onto the window and every named image set appears instantly, with @1x, @2x, and @3x variants shown side-by-side. No conversion step, no intermediate files.
- Batch export — export individual images or the entire catalog to a folder in one click, preserving the original filenames and scale suffixes.
- Quick Look thumbnails — hover any asset and you get a large preview without leaving the grid.
- Filter by name — type a substring to narrow a catalog with hundreds of assets down to the one you care about.
- Dark-mode-aware previews — the app renders assets against both light and dark backgrounds so you can immediately spot transparency issues.
- System .car support — you can open Apple's own Assets.car files buried in /System/Library/, which is genuinely useful for understanding how Apple renders certain UI elements.
For competitive analysis, design archaeology, or just satisfying curiosity about how a shipped Mac app is built, Asset Catalog Tinkerer is the only dedicated tool I've found that handles all of these scenarios without reaching for the command line.
Is Asset Catalog Tinkerer free?
Yes — completely free, and the full source code is available on GitHub under an open-source license. There is no premium tier, no IAP, and no nag screen. The developer, Guilherme Rambo, maintains it as an open community tool alongside other well-regarded projects like WWDC for macOS.
Who should use Asset Catalog Tinkerer?
iOS and macOS developers are the primary audience — specifically anyone who works with Xcode asset catalogs daily. If you've ever needed to recover an exported image from a project whose source .xcassets folder went missing, or wanted to confirm that a new build actually contains the right @3x assets before submitting to App Review, this tool saves real time.
UI designers working alongside developers will also find it useful for extracting final rendered assets from a shipped app bundle without needing Xcode installed. And systems programmers curious about macOS internals can use it to browse the rich asset libraries Apple ships with the OS itself.
It is not a general-purpose image manager — if you need to edit assets, you'll stay in Figma or Sketch. This is strictly an inspection and extraction tool, and it's excellent at exactly that.
How does Asset Catalog Tinkerer compare to using the command line?
The built-in alternative is assetutil --info, which dumps a JSON manifest, and a handful of community scripts that can extract individual images. Both require knowing the exact command flags and produce no visual feedback. Asset Catalog Tinkerer wraps that entire workflow in a native SwiftUI window, gives you instant previews, and lets you export assets without writing a single line of shell script. For occasional use the GUI wins decisively; for bulk automated pipelines where you're processing hundreds of .car files in CI, the command line still has its place — but those two use-cases rarely overlap.
What are the best Asset Catalog Tinkerer alternatives?
The realistic alternatives are thin. assetutil (ships with Xcode Command Line Tools) is the closest feature-equivalent but is entirely terminal-based. Sim Genie and Sherlock surface some asset metadata as part of broader developer workflows, but neither is designed for bulk catalog inspection. For general app-bundle archaeology, FileMerge or a hex editor get you nowhere near the visual clarity of Asset Catalog Tinkerer. In short: for this specific task, there is no polished GUI rival.
