Why the Mod's Time Differs From the F3 Day Counter

Two Different Clocks

Vanilla F3 shows in-game days elapsed. One in-game day is 20 real minutes, so players multiply days by 20 to estimate time. But that math breaks the moment you use /time set, sleep repeatedly, or run mods that change the day cycle. World Play Time instead tracks the actual time you've had the world open, so it doesn't care what the in-game clock says.

When They'll Disagree

• You used /time set day or /time set night to skip ahead.
• You slept through many nights in a row.
• A datapack or mod altered the day length.
• You left the world paused or in a menu — check whether your setup counts that.

Which to Trust

For "how many hours have I actually played this world," trust the mod's tag. For "how many in-game days have passed for mob spawning or weather," trust F3. They answer different questions.

If the numbers look wildly off, load the world once more so the mod can update its stored value, then return to the selection screen.