Roblox day and night cycle script

Where to put it

Script — ServerScriptService > DayNight (Script). It runs on the server, so players can't change what it does.

1. Insert a Script into ServerScriptService and paste the code. Change DAY_LENGTH_MINUTES to taste.

The script

local Lighting = game:GetService("Lighting")
local RunService = game:GetService("RunService")

local DAY_LENGTH_MINUTES = 12 -- one full 24-hour day
local hoursPerSecond = 24 / (DAY_LENGTH_MINUTES * 60)

RunService.Heartbeat:Connect(function(dt)
	Lighting.ClockTime = (Lighting.ClockTime + dt * hoursPerSecond) % 24
end)

How it works

• ClockTime is the in-game hour from 0 to 24; Roblox moves the sun, moon and sky to match.
• Heartbeat runs every frame, so the change is smooth instead of jumping.
• Running it on the server keeps every player at the same time of day.

Variations

local wasNight = false
Lighting:GetPropertyChangedSignal("ClockTime"):Connect(function()
	local isNight = Lighting.ClockTime >= 18 or Lighting.ClockTime < 6
	if isNight ~= wasNight then
		wasNight = isNight
		for _, light in workspace.StreetLights:GetDescendants() do
			if light:IsA("PointLight") then light.Enabled = isNight end
		end
	end
end)

Common mistakes

• Changing TimeOfDay as a string every frame — ClockTime is a number and much simpler.
• Running the cycle in a LocalScript: each player sees a different time.
• Nights that are too dark to play: raise Lighting.Ambient or OutdoorAmbient a little.