Building a roblox stamina bar script is one of those "aha!" moments for many developers because it instantly makes a game feel more professional and balanced. Think about it—without some kind of limit on movement, players can just hold down the shift key and zoom across your entire map in seconds, completely bypassing all the cool obstacles or encounters you spent hours designing. By adding a stamina system, you're not just adding a bar to the screen; you're adding a layer of strategy.
In this guide, we're going to walk through how to set this up from scratch. We'll cover the visual side (the GUI), the logic behind sprinting, and how to make the bar actually look smooth when it drains and refills. You don't need to be a coding wizard to follow along, but having a basic grasp of how scripts work in Roblox Studio will definitely help.
Setting Up the Visuals (The GUI)
Before we touch a single line of code, we need something for the player to look at. A roblox stamina bar script won't do much if there's no visual feedback. Head over to the StarterGui folder in your Explorer window.
- Insert a ScreenGui and name it something like "StaminaGui".
- Inside that, add a Frame called "Background". This will be the border or the "empty" part of the bar.
- Inside the "Background" frame, add another Frame and call it "Fill". This is the part that will actually change size as the player sprints.
Make the "Fill" frame a bright color like green or yellow, and set its size to {1, 0, 1, 0} so it completely fills the background frame. A little tip: change the AnchorPoint of the Fill frame to 0, 0.5 and its position to 0, 0, 0.5, 0. This ensures that when we change its width, it shrinks toward the left side rather than the center.
The Logic Behind the Script
Now for the fun part. We're going to use a LocalScript for this. Why a LocalScript? Because things like UI updates and player input (like pressing the Shift key) are best handled on the client side to ensure there's no lag between the player pressing a button and the bar moving.
To get started, place a LocalScript inside your "StaminaGui". Let's start by defining our variables. We need to keep track of the player's max stamina, their current stamina, and how fast it regenerates.
```lua local player = game.Players.LocalPlayer local character = player.Character or player.CharacterAdded:Wait() local humanoid = character:WaitForChild("Humanoid") local userInputService = game:GetService("UserInputService") local runService = game:GetService("RunService")
local stamina = 100 local maxStamina = 100 local sprintSpeed = 24 local walkSpeed = 16 local isSprinting = false ```
It's always better to keep these numbers at the top of your script. That way, if you decide later that 100 stamina is too little, you don't have to hunt through fifty lines of code to find the number—you just change it once at the top.
Making the Player Sprint
The core of our roblox stamina bar script is detecting when the player wants to run. We'll use UserInputService to check for the Left Shift key.
When the player presses Shift, we check if they have enough stamina. If they do, we boost their WalkSpeed. When they let go, we set it back to normal. But wait—we also need to check if they are actually moving! There's no point in draining stamina if the player is just standing still holding the Shift key.
```lua userInputService.InputBegan:Connect(function(input, processed) if processed then return end if input.KeyCode == Enum.KeyCode.LeftShift then isSprinting = true end end)
userInputService.InputEnded:Connect(function(input) if input.KeyCode == Enum.KeyCode.LeftShift then isSprinting = false end end) ```
The processed check is important. It tells the script to ignore the input if the player is currently typing in the chat. Without it, every time someone types a capital letter using Shift, their character would start sprinting!
Managing Stamina Depletion and Recovery
Now we need a loop that runs constantly to update the stamina values. The RunService.Heartbeat event is perfect for this because it runs every frame. Inside this loop, we'll handle three main states: 1. Sprinting: If isSprinting is true and the player is moving, decrease stamina. 2. Regenerating: If the player isn't sprinting, slowly increase stamina back to the max. 3. Exhausted: If stamina hits zero, force the player to stop sprinting until they've recovered a bit.
Here's where a little bit of math comes in. We don't want the bar to just "snap" to a new size; we want it to feel fluid.
```lua runService.Heartbeat:Connect(function(deltaTime) local moveDirection = humanoid.MoveDirection.Magnitude
if isSprinting and moveDirection > 0 and stamina > 0 then stamina = math.max(0, stamina - (10 * deltaTime)) humanoid.WalkSpeed = sprintSpeed else stamina = math.min(maxStamina, stamina + (5 * deltaTime)) humanoid.WalkSpeed = walkSpeed end -- Update the UI local scale = stamina / maxStamina script.Parent.Background.Fill:TweenSize(UDim2.new(scale, 0, 1, 0), "Out", "Linear", 0.1, true) end) ```
Notice the use of deltaTime. This is a professional trick that ensures the stamina drains at the same speed regardless of whether the player has a super-fast PC or a laggy phone. If you just subtracted 0.1 every frame, someone with 144 FPS would run out of stamina way faster than someone with 30 FPS!
Adding Polish with TweenService
While the basic script works, we want it to look good. Right now, the bar might flicker or jump around if the connection is slightly unstable. Using TweenService for the UI is okay, but for a roblox stamina bar script, you might want the bar to change colors when it's low.
Imagine the bar turning red when the player is under 20% stamina. It's a small touch, but it tells the player, "Hey, you're about to run out of breath!" without them having to stare directly at the number.
You can also add a "cooldown" period. If the player completely empties the bar, you could prevent them from sprinting again until it reaches at least 30%. This prevents that annoying "stutter-stepping" where a player taps the shift key repeatedly to move slightly faster while at 1% stamina.
Handling Character Respawns
One thing that trips up a lot of new developers is what happens when the player dies. By default, the StarterGui resets when a character respawns, but sometimes the script loses its reference to the new Humanoid.
To fix this, you can wrap your main logic in a function that triggers every time player.CharacterAdded fires. This ensures that the roblox stamina bar script stays linked to the current body the player is controlling.
Another tip: set the ResetOnSpawn property of your ScreenGui to true if you want a fresh bar every life, or false if you want the player's exhaustion to persist through death (though that might be a bit harsh for most games!).
Common Pitfalls to Avoid
- Server vs. Client: Don't try to handle the UI animations on a Server Script. It will look choppy and laggy for the player. Keep the visuals on the LocalScript.
- Infinite Sprinting: Make sure you're checking
humanoid.MoveDirection. If you don't, players will just sit in a corner holding Shift to drain their stamina for no reason, or worse, they might find a way to exploit the speed boost while standing still. - The "Flying" Glitch: Sometimes, increasing walk speed too much can interact weirdly with Roblox physics if the player is jumping. Test your speeds! Usually, anything between 20 and 28 is a "natural" feeling sprint.
Wrapping It Up
Adding a roblox stamina bar script is a fantastic way to improve the "game feel" of your project. It's a simple mechanic that bridges the gap between a basic tech demo and a real, playable game. Whether you're making a horror game where running away is life or death, or an RPG where stamina is used for special attacks, the foundation is the same.
Start with the basics, get the bar moving, and then start tweaking the numbers. Maybe your game needs a faster regen? Maybe sprinting should be even faster but drain the bar in three seconds? The beauty of writing your own script is that you have total control over the balance. Now get into Studio and start experimenting!