Undertale Cheat Codes

No cheat codes exist (Tips)

Undertale has no typed codes. Its famous 'cheats' are the name-entry Easter eggs and the file-edit 'dirty hacker' gag — both below are real, verified.

No built-in cheat codes exist for this game. See the entry description for what actually works on each platform.

Hard Mode: name yourself Frisk (Easter Egg)

Naming the fallen human 'Frisk' activates Hard Mode (tougher enemies, only the Ruins' story expanded).

Frisk

No built-in cheat codes exist for this game. See the entry description for what actually works on each platform.

Name Easter eggs (Easter Egg)

Entering canonical character names triggers unique flavor text (e.g. 'Sans' → 'that's a good name for a shopkeeper' gag, 'Toriel'/'Asgore' give mother/father comments). Full list on the Undertale wiki.

No built-in cheat codes exist for this game. See the entry description for what actually works on each platform.

'Dirty hacker' file edit (Easter Egg)

Editing your save file (file0/undertale.ini) to skip progress triggers Flowey calling you a dirty hacker — the game responds to cheating with condescension.

No built-in cheat codes exist for this game. See the entry description for what actually works on each platform.