Xcode cleanup · Updated September 14, 2026 · 8 min read

How to delete old Xcode Simulator runtimes on Mac

Remove runtimes through Xcode when possible. Use simctl for unavailable simulator devices; do not manually erase random CoreSimulator folders.

Quick answer: open Xcode → Settings → Components (or Platforms, depending on Xcode version), locate an installed simulator runtime you no longer test against, and remove it. Then run xcrun simctl delete unavailable to remove device records whose runtimes are gone.

Runtime, device, and device data are different

Item	Meaning	Safe removal path
Runtime	The installed iOS, watchOS, tvOS, or visionOS simulator platform.	Xcode Settings.
Simulator device	A configured virtual device.	Devices and Simulators or `simctl`.
Device data	Apps, test data, and settings inside a simulator.	Erase the selected simulator only.

1. Measure and list simulators

xcrun simctl list runtimes
xcrun simctl list devices
du -sh ~/Library/Developer/CoreSimulator

These commands list registered runtimes and devices, then measure CoreSimulator storage. du does not delete anything.

2. Remove old runtimes in Xcode

Quit running Simulator instances.
Open Xcode Settings and choose Components or Platforms.
Keep every OS version required by your test matrix.
Remove only a runtime you no longer need.

Removing a runtime means you cannot boot simulators for that OS until it is downloaded again. It does not delete projects or source repositories.

3. Delete unavailable device records

xcrun simctl delete unavailable

This asks CoreSimulator to delete devices that refer to runtimes no longer available. It is narrower than recursively deleting ~/Library/Developer/CoreSimulator.

Before removing a simulator: export any test data, screenshots, or app state you still need. Erasing or deleting a simulator destroys the apps and data inside that virtual device.

When not to clean

Keep older runtimes when your team supports that OS, reproduces version-specific bugs, produces screenshots on it, or runs local UI tests against it.

Related Xcode storage

Simulator runtimes are distinct from build intermediates and distribution archives. Read the Xcode Derived Data guide and the Xcode archives guide. The developer storage overview covers other tools.

Find large developer folders first.
TrimyMac provides a visual storage review so you can choose candidates instead of deleting broad Library directories.

Source

Workflow checked against Apple's Xcode and Simulator tooling documentation on September 14, 2026.