Make A Shift to Sprint Script

What is a 'Shift to Sprint' script? A shift to Sprint script is a script which allows the players speed to increase when the 'Shift' key is pressed on their keyboard.

The Script So first we want to add a LocalScript into StarterGui

And then we open the script and make a few variables to begin with.

local inputService = game:GetService("UserInputService")

Great! Now we have a variable for the UserInputService! Now let's make another variable!

local inputService = game:GetService("UserInputService")
local plr = game.Players.LocalPlayer

This one is for the player.

local inputService = game:GetService("UserInputService")
local plr = game.Players.LocalPlayer
local char = plr.Character or plr.CharacterAdded:wait()

This variable is for the Player's Character. Now let's start making the speed variables for the player.

local inputService = game:GetService("UserInputService")
local plr = game.Players.LocalPlayer
local char = plr.Character or plr.CharacterAdded

local normalSpeed = 16
local sprintSpeed = 25

Awesome! now let's make a variable to see if the player is sprinting or not.

local inputService = game:GetService("UserInputService")
local plr = game.Players.LocalPlayer
local char = plr.Character or plr.CharacterAdded

local normalSpeed = 16
local sprintSpeed = 25
local sprinting = false

Cool! Now we'll start the script To start off we'll see if the input has began, and if it has, connect a function.

inputService.InputBegan:Connect(function(key)

Cool! Now we'll set the variable "Running" which we created earlier to true

inputService.InputBegan:Connect(function(key)
    if key.KeyCode == Enum.KeyCode.LeftShift or key.KeyCode == RightShift then
        sprinting = true

Awesome! Now let's see if it is the Character, and if it is then change the walkSpeed!

inputService.InputBegan:Connect(function(key)
    if key.KeyCode == Enum.KeyCode.LeftShift or key.KeyCode == RightShift then
       sprinting = true
       if char then
            char.Humanoid.WalkSpeed = sprintSpeed

Great! Now we need to make it so that when we let go of 'Shift', we stop sprinting. So type this.

inputService.InputEnded:Connect(function(key)
    if key.KeyCode == Enum.KeyCode.LeftShift or key.KeyCode == Enum.KeyCode.RightShift then
        running = false
        if char then
            char.Humanoid.WalkSpeed = normalSpeed

Great! Now Let's put it all together!

local inputService = game:GetService("UserInputService")
local plr = game.Players.LocalPlayer
local char = plr.Character or plr.CharacterAdded:Wait()

local normalSpeed = 10
local sprintSpeed = 18
local running = false

inputService.InputBegan:Connect(function (key)
    if key.KeyCode == Enum.KeyCode.LeftShift or key.KeyCode == Enum.KeyCode.RightShift then
        running = true
        if char.Humanoid then
            char.Humanoid.WalkSpeed = sprintSpeed
        end
    end
end)

inputService.InputEnded:Connect(function (key)
    if key.KeyCode == Enum.KeyCode.LeftShift or key.KeyCode == Enum.KeyCode.RightShift then
        running = false
        if char.Humanoid then
            char.Humanoid.WalkSpeed = normalSpeed
        end
    end
end)

Now you should have Shift to Sprint in your ROBLOX game!