SimCleaner for Xcode

A Mac app that shows every Xcode simulator on your disk, how much space each one takes, and cleans up the simulators and Xcode caches you don't need.

simcleaner.com · Mac App Store · SimCleaner Pro · Build from source · MIT License

Simulators pile up. Every Xcode release adds a new batch, test runs clone devices, SwiftUI Previews make their own, and after a year it's common to find 50–100 GB sitting in ~/Library/Developer. DerivedData and device support files add more on top. Xcode has no single screen that shows all of it. SimCleaner does.

What it does

• Every simulator (iPhone, iPad, Apple Watch, Apple TV, Vision Pro) is in one table you can search by name, model, iOS version, UDID or the name of an installed app.
• A bar at the bottom of every page shows what simulators, runtimes, DerivedData, device support files, agent workspaces and simulator caches take, next to the space you have left. Click a colour to open the page that cleans it.
• Each simulator shows its size, so the big ones stand out. Because simulators share files through APFS clones, deleting one can free less than its size; when that matters, you see the least and the most a cleanup frees.
• Cleanups add up in a "Freed about" total next to the bar: an estimate that counts only what is gone from disk, each item by the bytes it held alone where APFS can tell. It starts again an hour after your last cleanup.
• You see when you last used each simulator. Devices Xcode created but never booted say "Never launched".
• The apps inside each simulator are listed with how much space each app and its data take, and you can open an app's Documents, Caches or Preferences folder in Finder.
• Smart Cleanup removes in one click what Xcode makes again by itself and nobody used for the period you pick: DerivedData of projects you haven't opened, device support for OS versions your devices have moved on from, Preview and test simulators, and old agent workspaces. A date SimCleaner can't read never counts as old, and each item is checked again right before it goes.
• Simulators you test in stay suggestions you act on yourself: ones you haven't used for a few weeks, ones that can't run because their runtime is gone, and folders no simulator owns.
• Xcode caches get their own page: DerivedData, device support files, and the build folders coding agents leave behind through XcodeBuildMCP or MobileBuildMCP.
• Deleting, erasing, shutting down, duplicating and renaming go through Xcode's own simctl, so Xcode and Device Hub see the change right away. SimCleaner asks before anything destructive.
• One build can go onto several simulators at once.
• Any simulator opens in Device Hub (Xcode 27) or Simulator, and you can reveal its folder in Finder.

Simulators	Smart Cleanup	Xcode caches

_{Screenshots use sample projects.}

Two editions

SimCleaner comes in two editions. Both are free, both are built from this repository, and they share the same code and the same window. The difference is the App Sandbox.

Every app in the Mac App Store runs in the sandbox. Inside it, macOS keeps the app away from the CoreSimulator service that mounts simulator runtimes, so a sandboxed app can't start a simulator or delete a runtime, and Apple no longer approves the exception that would allow it. Those features live in SimCleaner Pro, a separate download that runs outside the sandbox and is notarized by Apple.

	App Store	Pro
Price	Free	Free
Requires	macOS 15.6 or later	macOS 27 and Xcode 27
Install and updates	Mac App Store	DMG from Releases, then updates itself
Simulators, sizes, apps, last use	✓	✓
Delete, erase, shut down, duplicate, rename	✓	✓
Smart Cleanup and suggestions	✓	✓
DerivedData, device support files, agent workspaces	✓	✓, and marks DerivedData whose project is gone
Start a simulator	Opens it in Device Hub or Simulator	Starts it, then opens it
Remove an app from a simulator	Running simulators	Starts the simulator for a moment
Install one build on several simulators	Running simulators	Starts each one, installs, shuts it down
Delete runtimes	Shows them and where to delete them	✓
simcleaner command line tool		✓
Tip jar	✓

If you clean up simulators by hand now and then, the App Store edition is enough, and it updates itself. Pro is for runtimes, for starting simulators without leaving the app, for installing one build on many of them, and for scripts and coding agents.

The App Store edition mentions Pro only next to a feature it can't do, with a link back here. Download SimCleaner Pro for macOS 27 and Xcode 27; after that it updates itself. You can also build it from source with the SimCleaner Pro scheme.

Command line

SimCleaner Pro includes simcleaner, a command line tool with the same rules as the app. To put it on your PATH:

sudo ln -sf "/Applications/SimCleaner Pro.app/Contents/MacOS/simcleaner" /usr/local/bin/simcleaner

simcleaner                          # where the space goes: simulators, runtimes, caches
simcleaner suggest                  # what's worth cleaning, and the command that does it
simcleaner list --running --json
simcleaner caches list
simcleaner caches remove --suggested --yes
simcleaner runtimes list
simcleaner erase 35D56CF8-69AC-4DD7-BD86-98F388A27A9B --yes
simcleaner install MyApp.app --to "iPhone 18 Pro" "iPad Air 13-inch (M3)"

Commands that delete something (erase, delete, caches remove, runtimes delete) print what they would do and exit with code 2 until you add --yes. install exits with 1 unless every simulator you named got the app and was left running or shut down the way it was found; its JSON says what happened to each one. Simulators are named by UDID or by exact name; a name that matches more than one simulator is refused. Listings take --json, and the JSON keys stay stable, so scripts and coding agents can rely on them. What SimCleaner couldn't read is never reported as zero: storage prints "couldn't read", and its JSON marks the line "coverage": "unreadable" and leaves out the sizes; a line marked "partial" may be missing some folders. runtimes list exits with 1 when it can't read the runtimes.

Where it looks

Xcode keeps simulators in four places, all inside ~/Library/Developer:

Folder	What's in it	Label in SimCleaner
CoreSimulator/Devices	Simulators you create in Xcode or with simctl	—
Xcode/UserData/Previews/Simulator Devices	Devices created for SwiftUI Previews	Previews
XCTestDevices	Clones made for parallel test runs	Test clone
XCPGDevices	Devices used by Swift Playgrounds	Playground

Xcode caches come from Xcode/DerivedData, the Xcode/… DeviceSupport folders, and XcodeBuildMCP/workspaces and MobileBuildMCP/workspaces.

The App Store edition asks for access the first time it runs. Choose ~/Library/Developer: one grant covers all of these folders. If you pick a folder above or below it (your home folder, CoreSimulator, Devices), SimCleaner still finds the simulators inside, but Xcode caches need the Developer folder itself. Pro reads ~/Library/Developer directly and doesn't ask.

Simulator runtimes

A simulator is a folder of device data: apps, settings, caches. The iOS system it runs on is a separate download called a runtime. A runtime takes several gigabytes, and all simulators of that iOS version share it, so deleting simulators doesn't free that space.

SimCleaner Pro lists runtimes with their size, when a simulator last used each one and how many simulators depend on it, and deletes the ones you choose through CoreSimulator. The App Store edition lists them with their size and how many simulators use them, but not when they were last used, and can't delete them. Use Xcode → Settings → Components for that, or xcrun simctl runtime delete RUNTIME_ID in Terminal with an ID from xcrun simctl runtime list.

macOS 27 and Xcode 27

Version 1.2 fixes what broke with the 2026 releases:

• Xcode 27 renamed the "last used" date that CoreSimulator writes (lastBootedAt became lastUsedAt). Older versions of SimCleaner showed "Never launched" for every simulator. Both keys are read now.
• Simulators are found in all four folders listed above, not only the one you picked.
• The folder picker opens at your real ~/Library/Developer. Inside the App Sandbox the default location used to point at the app's own container.
• When a folder has no simulators, the app now tells you why (wrong folder, unreadable folder, or runtimes) instead of just showing "0 found".

Privacy

Neither edition collects analytics or talks to a server of its own. The App Store edition runs in the App Sandbox without network access; its optional tip jar goes through Apple's StoreKit. Pro runs outside the sandbox so it can start simulators and delete runtimes. Its one network request is the update check: once a day Sparkle reads https://simcleaner.com/updates/appcast.xml, and it installs an update only if the download and the feed are both signed with SimCleaner's key. Check for Updates Automatically in the SimCleaner Pro menu turns the check off. Both delete only what you select: simulators and runtimes through Xcode's simctl, cache folders only inside ~/Library/Developer. If simctl can't be used (Xcode missing, the license not accepted, a timeout), SimCleaner doesn't delete simulators at all while CoreSimulator is on the Mac, because something may still be using them.

Build from source

Requirements: Xcode 27. The App Store edition runs on macOS 15.6 or later, Pro on macOS 27.

git clone https://github.com/Stepanokdev/SimCleaner.git
cd SimCleaner
open SimCleaner.xcodeproj

Choose the XCode Devices scheme for the App Store edition or SimCleaner Pro for Pro, set your own team under Signing & Capabilities, and run. The Pro scheme also builds simcleaner and copies it into the app; the SimCleaner scheme builds all three and runs the app tests. Without a signing certificate you can still build and test with ad-hoc signing:

xcodebuild -project SimCleaner.xcodeproj -scheme "XCode Devices" -destination 'platform=macOS' \
  CODE_SIGN_IDENTITY=- CODE_SIGN_STYLE=Manual DEVELOPMENT_TEAM= PROVISIONING_PROFILE_SPECIFIER= test

swift test --package-path Packages/SimCleanerKit

The tests build throwaway ~/Library/Developer-shaped folders on disk and talk to a fake simctl, so they never touch your real simulators. Two integration tests use the real one: the package test creates, clones, erases and deletes a simulator in a throwaway device set, and the app test checks what simctl can do from inside the sandbox. They run only with SIMCLEANER_INTEGRATION=1 (TEST_RUNNER_SIMCLEANER_INTEGRATION=1 for xcodebuild test).

Project layout

Folder	What it does
Packages/SimCleanerKit	Everything that isn't UI: finding simulators, APFS-aware sizes, simctl, cleanup rules, Xcode caches, runtimes, installs. Both editions and the CLI use it.
XCode Devices/	The window both editions share: sidebar, simulator table, details, cleanup pages, install sheet
Editions/AppStore/	What only the App Store edition has: sandbox entitlements, tip jar, rating prompt
Editions/Pro/	What only Pro has: its entitlements, the command line tool sheet and Sparkle updates
CLI/	The simcleaner command line tool
XCode DevicesTests/	Tests for the app's view model and page layout

Each edition folder defines the same few symbols (AppEdition.current, EditionToolbarButton, EditionCommands, EditionHooks), so the shared code has no #if. Features that depend on the sandbox check Capabilities at runtime instead.

Contributing

Bug reports and pull requests are welcome, here or by email to stepanokdev@gmail.com. In the app, Help › Send Feedback starts that email with the app and macOS versions already filled in. If simulators are missing or dates look wrong, please add your Xcode version. The output of xcrun simctl list devices -j helps a lot.

License

MIT, for both editions. See LICENSE.