I've spent way too many hours tweaking my roblox studio humanoid running script just to get the speed transition feeling exactly right. It's one of those foundational things that sounds simple on paper—you just press a button and go faster, right?—but if you want it to feel professional and not janky, there are a few specific things you need to handle. Whether you're building a high-intensity horror game where you need to sprint away from a monster, or just a basic simulator, getting the running mechanics down is super important for the player experience.
When we talk about a running script, we're usually looking at three main things: detecting when the player hits the shift key, changing the WalkSpeed of the Humanoid, and maybe adding some "juice" like field-of-view changes or stamina bars so the player can't just sprint forever.
Getting the Basics Down
In Roblox, every player character has a Humanoid object. This object is basically the brain of the character's physical body. It controls how fast they walk, how high they jump, and how much health they have. By default, most characters walk at a speed of 16. To make them "run," we basically just need a script that tells the Humanoid, "Hey, change that 16 to a 25 for a bit."
The best place to put a roblox studio humanoid running script is inside StarterCharacterScripts. Why? Because scripts in that folder automatically clone themselves into the player's character every time they respawn. If you put it in StarterPlayerScripts, you have to do extra work to find the character every time they die and come back. Keeping it in StarterCharacterScripts just makes our lives easier.
Setting Up the LocalScript
You'll want to create a new LocalScript and name it something like "SprintScript." We use a LocalScript because input (like pressing a key) happens on the player's computer, not the server. If we tried to do this on a server script, there would be a tiny delay between pressing the key and actually moving, which feels terrible in a fast-paced game.
Inside that script, we need to grab the UserInputService. This is the service that listens for keyboard presses, mouse clicks, or even controller triggers. Here's the basic logic: we check when LeftShift is pressed down, and we check when it's released.
```lua local UIS = game:GetService("UserInputService") local player = game.Players.LocalPlayer local character = script.Parent local humanoid = character:WaitForChild("Humanoid")
local walkSpeed = 16 local runSpeed = 28
UIS.InputBegan:Connect(function(input, processed) if processed then return end if input.KeyCode == Enum.KeyCode.LeftShift then humanoid.WalkSpeed = runSpeed end end)
UIS.InputEnded:Connect(function(input, processed) if input.KeyCode == Enum.KeyCode.LeftShift then humanoid.WalkSpeed = walkSpeed end end) ```
This is the "bare bones" version. It works, but it's a bit "snappy." The speed changes instantly, which can look a little robotic.
Adding Some Polish with TweenService
If you want your game to feel "high quality," you shouldn't just snap the speed from 16 to 28. It's better to have a tiny ramp-up. We can use TweenService for this. Instead of setting the speed directly, we "tween" it over a fraction of a second. This makes the transition feel much smoother, like the character is actually accelerating.
I usually set the tween time to something like 0.2 or 0.3 seconds. It's fast enough that the player feels the response immediately, but slow enough to remove that digital "on/off" feeling.
Also, don't forget about the camera! When you run in real life (or at least in movies), your vision feels a bit wider. In Roblox, we can mimic this by changing the FieldOfView (FOV) of the CurrentCamera. When the player starts sprinting, we can bump the FOV from 70 to 80 or 90. It gives a great sense of speed even if the character isn't actually moving that much faster.
Handling Stamina (Because Running Forever is Cheating)
Unless you're making a casual hangout game, you probably don't want players sprinting at full speed across the entire map without a break. Adding a stamina system to your roblox studio humanoid running script adds a layer of strategy.
To do this, you'll need a variable for Stamina and maybe a MaxStamina. You'd then use a while loop or a Heartbeat connection to drain that stamina while the player is running.
The logic usually looks like this: 1. Is the player holding Shift? 2. Is the player actually moving? (Check humanoid.MoveDirection.Magnitude > 0). 3. Do they have stamina left?
If all three are true, they run. If they run out of stamina, you force them back to walkSpeed until it recharges. It's a simple loop, but it makes the game feel much more like a "game." I've seen a lot of beginners forget the "is the player moving" check. If you don't check that, the player will drain all their stamina just by holding Shift while standing still, which is super annoying for the person playing your game.
Common Pitfalls and Troubleshooting
One thing that tripped me up when I first started was the "processed" parameter in UserInputService. You'll notice in my little code snippet I wrote if processed then return end. This is super important. "Processed" basically means the player is doing something else with their keyboard—like typing in the chat box.
Without that line, every time a player types a capital letter (using Shift) in the chat, their character will start sprinting in the background. It's a small detail, but it's the difference between a script that feels "pro" and one that feels like a bug.
Another issue is animation. If you have a custom walk animation and a custom run animation, Roblox usually tries to blend them based on speed. However, if your speed is set too high or too low, the legs might look like they're sliding on ice. You might need to go into your Animate script (the one Roblox puts in the character automatically) and make sure your animation speeds match your script's WalkSpeed.
Making it Mobile Friendly
We've been talking about the Shift key, but what about mobile players? They don't have a keyboard. If you want your roblox studio humanoid running script to work for everyone, you might want to add a GUI button on the screen for mobile users.
You can use ContextActionService for this instead of UserInputService. It's a bit more advanced, but it allows you to create a virtual button that only appears on touch devices. It binds the same function to a keypress and a screen tap, so you don't have to write the code twice.
Final Thoughts
Building a roblox studio humanoid running script is a great "Level 1" scripting project. It touches on input, player characters, and properties. Once you get the hang of changing the WalkSpeed, you can start adding all the bells and whistles—stamina bars, screen shakes, heavy breathing sound effects, and wind particles.
The cool thing about Roblox is how much control you have over the Humanoid. Once you're comfortable with sprinting, you can use the same logic to create crouching (lowering WalkSpeed and changing the CameraOffset) or even power-ups that give the player a temporary speed boost. Just remember to keep the player's experience in mind—smooth transitions and bug-free input handling go a long way in making your game feel fun to play.
Keep experimenting with the values! Sometimes a runSpeed of 30 feels too fast, and sometimes 20 feels too slow. It all depends on the scale of your map. Happy scripting!