Where Are Binding of Isaac Save Files Located?
Where Isaac keeps live saves in Steam userdata and automatic dated backups in Documents, and which one the game reads.
Last updated
The Binding of Isaac reads live saves from Steam userdata under app ID 250900, while dated automatic backups accumulate in Documents\My Games\Binding of Isaac Afterbirth+. Two locations, two roles: userdata is the game truth, Documents is the rescue archive.
Slot files are named persistentgamedata1-3 with era prefixes, and the game recreates missing ones as blank slates on launch. That behavior turns a sync hiccup into an apparent wipe: the progress is usually intact in the newest dated backup, one rename away.
Where The Binding of Isaac stores this, by platform
C:\Program Files (x86)\Steam\userdata\[SteamID]\250900\remote
Replace the Steam root and account ID with your own. The numbered folder after userdata is your account. Documents holds dated backups only; the game never reads those directly.
Frequently asked questions
My Isaac save vanished. How do I restore from backup?
Find the dated backup (YYYYMMDD.abp_persistentgamedataN) in Documents, copy it over the live persistentgamedataN file in userdata, and strip the date prefix. Back up the live file first: restores that fail need a way back.
What do the abp_ prefixes and numbers mean?
They stack by generation: bare persistentgamedata for Rebirth, ab_ prefix for Afterbirth, abp_ for Afterbirth+. The number (1-3) is the save slot. Gamestate files beside them are suspended runs (the Continue option), not unlock progress.
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