Deleting chunks is the core job of MCA Selector: clear old terrain so it regenerates, remove corrupted chunks, or strip a world down to the parts players actually use. The operation itself is three clicks — the skill is in selecting exactly the right chunks, because deletion is instant and cannot be undone.
Back up your world first: MCA Selector writes deletions and NBT changes straight to disk the moment you confirm them — there is no undo and no File → Save step to catch a mistake. Close Minecraft (and stop your server, if the world is on one), then copy the whole world folder somewhere safe before you edit.
Step 1: Open the world and pick the right selection mode
Choose File → Open World and select the world folder (the one directly containing region/poi). Then zoom: zoom in until you see the chunk grid if you want to delete individual chunks, or zoom out to the region grid if you deliberately want to delete whole regions. This is the mistake behind most “I deleted too much” stories — at region zoom, a single drag can mark 1,024 chunks per region square. The map grid on screen always tells you which mode you are in.
Step 2: Select the chunks to delete
Click or drag to select single chunks, hold Shift to paint a free-form area. Use Selection → Invert if it is easier to mark what you want to keep and delete the rest, and Selection → Clear to start over. To select by properties instead of by hand — for example every chunk with an old DataVersion — use the chunk filter, which can apply the same deletion to every chunk matching your conditions. Before deleting, consider Selection → Export selection to save the selection as a CSV record of what you are about to remove. The selection tools guide covers all of this in depth.
Step 3: Delete — it happens immediately
Choose Selection → Delete selected chunks and confirm. That is the whole procedure, and it is also the point of no return: as the official documentation puts it, chunks are deleted in the original files, “this operation is instant and there is no going back.” There is no recycle bin, no undo, and no File → Save step afterwards — the chunks are already gone from disk when the dialog closes.
Step 4: Verify the result
- Close MCA Selector, then open the world in Minecraft.
- Fly to the area you edited. Deleted areas appear as void until you enter them.
- Walk or fly into the cleared area so the game regenerates it, and check the borders between deleted and kept chunks for cliffs or cut-off builds.
- Only now — once the world checks out — delete your safety backup, or keep it until the next backup cycle.
Deleting a whole dimension or old regions
Everything above works per dimension: open the world, switch to the dimension you want to edit, and repeat. For bulk cleanups tied to a game update — deleting everything except your bases so new terrain generates — follow the dedicated world pruning workflow, and if your goal is fresh terrain in specific spots rather than removal, the reset chunks guide explains the regenerate-after-delete mechanic.
Mistake-proofing checklist
- Minecraft and any server using the world are fully closed.
- You have a dated backup copy of the whole world folder.
- The zoom level matches the selection unit you intend (chunks vs regions).
- The selection — not its inverse — is what gets deleted; re-check after using Invert.
- You exported the selection to CSV if the cleanup is large or hard to re-create.
Download MCA Selector 2.9
Everything in this guide works with the current release. Get the Windows installer, the cross-platform .jar, the macOS .dmg or the Linux .deb/.rpm from the MCA Selector download page — every button there points at the official GitHub release files and lists the SHA-256 checksum, with a clearly labelled site mirror as a fallback.
One last backup reminder: keep the copy of your world you made before editing until you have loaded the edited world in Minecraft and confirmed it looks right. Deletions and NBT changes in MCA Selector are permanent once applied.