- SimCleaner
- Guides
Where Xcode's gigabytes go
What each folder is, whether it's safe to delete, and how to do it by hand or with SimCleaner. Every command here was run on macOS 27 with Xcode 27.
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Why Xcode takes so much disk space, and how to get it back
Simulators, runtimes, DerivedData, device support, Previews and "System Data": what each one is, typical sizes, and the order to clean them in.
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How to delete simulator runtimes that won't go away
Settings › Components or simctl, why rm can't remove them, and the Xcode 27.0 bug that brought them back.
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How to delete old iOS simulators
Erase or delete, how to find the unused ones, and the one command for unavailable simulators.
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Is it safe to delete DerivedData?
Yes. You trade disk space for build time. Plus why CompilationCache.noindex keeps growing.
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Coding agents and Xcode disk space
Workspaces, DerivedData copies and simulators that agents leave behind, and what to keep.
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Can you delete iOS DeviceSupport?
Debug symbols from every device you connected, one folder per OS version. Which ones to keep.
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SwiftUI Preview devices and XCTest clones
Two sets of simulators Xcode creates for you and rarely cleans up.
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Deleted gigabytes, but free space barely moved
APFS clones, local snapshots and purgeable space, and how to tell what you actually freed.