Terraria has no cheat codes to type, but it does have a cheat mode built into the game. Journey Mode was designed for exactly that. You can research items and duplicate them endlessly, become immortal, freeze time and weather, and cut enemy spawns down to zero. There is no need to download any program, as all of it is the game's own power.
Terraria has no cheat console. Instead, choosing Journey Mode when you create a character opens a power menu in the game. This menu sits on the left side of the screen, and every cheat-like setting is there.
A Journey character can only enter a Journey world, and a normal character can only enter a normal world.
Journey Mode is available in the console versions too.
Journey Mode is available in the console versions too.
Pick Journey Mode when creating a character
Powers only work for Journey Mode characters. You cannot convert an existing character to Journey Mode later, so you need to create a new one.
Drop the item into the research slot, and once you reach the required amount it can be duplicated endlessly. The core feature of Journey Mode.
Every item you research sits in this menu in endless supply. Take as many as you want and use them.
Nothing can hurt you. In practice you do not die, including from enemy damage, falling and drowning.
Lock it to night or day. Ideal for keeping it daytime while you build.
Turns rain and wind on and off, so you can lock in the weather you want.
Pull it down to zero and no enemies spawn, push it to the max and they keep pouring in. The most used power while building.
Power menu > Difficulty Slider
Slide it anywhere from Journey to Master. Enemy health and damage change accordingly, and you can change it back at any time.
Power menu > Increased Placement Range
Boosts your block placement and item pickup range from 10×7 to 37×33 tiles. It is on by default and saves you from constantly moving while building.