Is It Safe to Delete Developer Data on Mac?

If you've run a storage scan and seen "Developer Data" listed as a major category, you're not alone. On a Mac where Xcode is installed, this bucket can quietly grow to 30, 50, even 100+ gigabytes.

The good news: most of it is safe to delete. The slightly more complicated answer: not all of it, and knowing the difference matters.

What "Developer Data" Includes

Developer data isn't one thing — it's a collection of several distinct categories, each with different cleanup rules.

Xcode Derived Data

Xcode stores compiled build artifacts in ~/Library/Developer/Xcode/DerivedData. Every time you build a project, Xcode caches the compiled output here so subsequent builds are faster.

These files are safe to delete. Xcode will rebuild them automatically the next time you open and build a project. The only cost is a longer first build after cleanup.^[1]

Derived data is typically the single largest item in this category — easily 5–20 GB on an active development machine.

iOS and iPadOS Simulator Images

Xcode downloads full operating system images for every simulator runtime you've ever used. An iPhone 17 simulator running iOS 18, an older iPad simulator, a watchOS runtime — each one is a multi-gigabyte download stored in /Library/Developer/CoreSimulator/Profiles/Runtimes.

These files are safe to delete if you no longer need to run that specific simulator version. Xcode will prompt you to re-download the runtime if you try to launch a simulator that needs it.^[2]

A developer who has tested across several iOS versions and device types can easily accumulate 30–60 GB here without realizing it.

Simulator Device Data

Separate from the runtime images, Xcode also stores data for each simulated device you've booted — installed apps, preferences, and state — in ~/Library/Developer/CoreSimulator/Devices.

This is safe to remove for simulators you're no longer using. Any simulator you boot again will be reset to a clean state.

CocoaPods Cache

CocoaPods stores a local cache of downloaded pod source files in ~/Library/Caches/CocoaPods. This is used to speed up pod install by avoiding repeat downloads.

Deleting it is safe. The cache will be rebuilt the next time you run pod install.^[3]

npm and Node.js Cache

If you do any JavaScript or Node.js development, npm maintains a cache in ~/.npm. Yarn uses ~/Library/Caches/Yarn. Both are safe to clear — running npm install or yarn in any project will repopulate the cache from the registry.

Xcode Archives

Xcode archives — .xcarchive bundles created when you archive a project for distribution — live in ~/Library/Developer/Xcode/Archives. These can be several hundred MB to a few gigabytes each.

Be careful here. If you need to re-submit a build to the App Store or re-export an IPA without rebuilding from source, you need the archive. Delete archives only if you're certain you have the source code and can rebuild.^[4]

Old Device Support Files

Xcode downloads device support files for every physical device you've connected, stored in ~/Library/Developer/Xcode/iOS DeviceSupport. These files enable on-device debugging and symbol lookup for a specific iOS version.

If you no longer have a device running that iOS version — or you don't do on-device debugging — these are safe to remove.

What Is and Isn't Safe: A Quick Reference

Category	Safe to Delete?	Notes
Derived Data	Yes	Rebuilt automatically on next build
Simulator Runtimes	Yes	Re-downloaded if needed
Simulator Device Data	Yes	Simulator resets to fresh state
CocoaPods Cache	Yes	Rebuilt on next pod install
npm / Yarn Cache	Yes	Rebuilt on next install
Xcode Archives	Careful	Only delete if you can rebuild from source
Device Support Files	Yes	Rarely needed after device update

How Much Space Can You Get Back?

On a Mac that has been running Xcode for a year or more without cleanup:

• Derived data: 5–20 GB
• Simulator runtimes: 10–60 GB
• Simulator device data: 2–10 GB
• Package manager caches: 1–5 GB
• Device support files: 2–8 GB

It's not unusual to reclaim 30–60 GB in a single cleanup pass on an active development machine.

The Risk of Doing This Manually

The standard advice is to clean derived data from inside Xcode (Product → Clean Build Folder) and manage simulators through Xcode's Platform settings. This works, but it's limited:

• Xcode's built-in cleanup doesn't touch CocoaPods, npm, or device support files
• Navigating to /Library/Developer/CoreSimulator/Runtimes and manually deleting simulator images requires knowing exactly which paths to target
• It's easy to accidentally remove something you still need

A More Reliable Approach

DiskCleaner scans Developer Data as a dedicated category — covering Xcode derived data, simulator images, device support files, CocoaPods cache, and npm cache. You see a full list with file sizes before anything moves, and everything goes to Trash (not permanent deletion), so you can recover anything you removed by mistake.

Final Take

Most developer data on a Mac is safely removable. Derived data, simulator runtimes, and package manager caches are all designed to be rebuilt on demand. The one real exception is Xcode archives — only remove those if you're confident you don't need to re-export or re-sign a previous build.

For any Mac that has had Xcode installed for more than a year, a single cleanup pass through developer data is one of the highest-yield storage wins available.