/fill and /clone: the 32,768 block limit and the modes that get around it
Both commands cap at 32,768 blocks per call and fail silently past it. Here are the hollow, outline and replace modes, the clone masks, and how to move a build bigger than the cap.
/fill and /clone share a hard limit that is not in the error message people expect: 32,768 blocks per command. That is 32×32×32. Go past it and the command refuses, which in a command block chain looks like nothing happening at all.
Working out whether you are over
The count is inclusive on both ends, so a region from 0 0 0 to 31 31 31 is exactly 32,768 — right at the cap. From 0 0 0 to 32 32 32 is 35,937 and fails.
blocks = (|x2-x1|+1) × (|y2-y1|+1) × (|z2-z1|+1)For anything larger, split into slabs and run several commands. Splitting on Y is usually easiest to reason about.
fill modes
| Mode | Does |
|---|---|
replace | default; optionally filter to one block type |
hollow | fills the outer shell, clears the interior to air |
outline | fills the outer shell, leaves the interior alone |
destroy | drops the existing blocks as items first |
keep | only fills air, never overwrites |
hollow versus outline is the pair people mix up. Building a glass box around an existing structure needs outline; hollow would delete what is inside it.
keep is the safe one for terrain — it will not eat anything already placed.
The filter form takes the block to replace last:
/fill ~ ~ ~ ~10 ~5 ~10 stone replace dirtThat replaces only dirt with stone and leaves everything else untouched.
clone modes and masks
/clone has two independent settings and the order matters:
Mask — replace (everything) or filtered <block> (only that block) or masked (skip air in the source).
Mode — normal, force (allow overlapping regions), or move (clear the source after copying).
/clone <begin> <end> <destination> masked normalmasked is what you want when stamping a build onto existing terrain — air in the source will not punch holes in the destination.
move is the one that surprises people: it deletes the original. There is no undo.
Overlap needs force
If source and destination overlap at all, normal refuses. force allows it, but the result depends on copy order and is rarely what you wanted. Cloning to a scratch area and back is more predictable.
Chunks must be loaded
Both commands only work on loaded chunks. A /fill reaching into unloaded terrain silently does nothing out there. For scripted builds, /forceload add the region first and remove it after — otherwise the same command works when you are standing nearby and fails when run from spawn.
Build any of these with the arguments in the right order, and the block count checked against the cap, in the World & Blocks Command Builder.