Setting up a roblox performance stats script is one of those things you usually don't think about until your game starts lagging for no apparent reason. We've all been there—you're testing a new feature, everything feels fine on your high-end PC, but then a player joins on a phone and suddenly the whole thing turns into a slideshow. Without some kind of real-time data, you're basically just guessing where the problem is. Is it the scripts? Is it the parts? Is it just a bad internet connection?
That's where a custom performance monitor comes in handy. While Roblox has its own built-in stats overlay (the one you see when you hit Shift+F5), it's not exactly pretty, and you can't really customize it to show only what your players need to see. Plus, if you're building a competitive game, you might want to give players a way to check their ping and FPS without digging through menus.
Why you should track your own stats
Honestly, the biggest reason to build your own roblox performance stats script is clarity. The default engine stats are cluttered with technical jargon that most players won't understand. If a player tells you "the game is laggy," that could mean ten different things. If you have a clean UI that shows them their FPS and Ping, they can give you a much better report.
Besides the player experience, it's a lifesaver for debugging. If you see the memory usage climbing steadily over twenty minutes, you know you've got a memory leak somewhere. If the FPS drops only when a certain move is used, you know exactly which script to go troubleshoot. It's about working smarter, not harder.
The core metrics that actually matter
When you're putting this script together, don't feel like you need to track every single heartbeat of the engine. Usually, there are only three or four numbers that actually tell you the story of how a game is running.
Frames Per Second (FPS)
This is the big one. It's the most obvious indicator of "smoothness." In Roblox, the cap is usually 60 FPS unless someone is using an external unlocker. If this number is dipping, it usually means the client's CPU or GPU is struggling to keep up with the rendering or the local scripts.
Ping (Latency)
Ping is all about the round-trip time it takes for data to go from the player to the server and back. This is measured in milliseconds (ms). High ping means the player is "lagging" in the traditional sense—teleporting around, hits not registering, or doors taking three seconds to open after clicking them.
Memory Usage
This is often overlooked but it's super important for mobile players. If your game uses 2GB of memory and the player only has a phone with 3GB of RAM, the Roblox app is probably going to crash. Keeping an eye on this helps you realize when your textures are too big or when you're not properly destroying objects.
Setting up the UI
Before we even touch a script, you need a place for these numbers to live. I usually recommend a ScreenGui in StarterGui. Keep it subtle. Maybe a small bar at the top or a tiny box in the bottom right corner.
You'll want a TextLabel for each stat. Name them something obvious like FPSLabel, PingLabel, and MemLabel. I like to use a dark, semi-transparent background for the labels so the white text is readable regardless of what's happening in the game world.
Writing the roblox performance stats script
Now for the actual coding. You'll want to put this in a LocalScript because performance stats are client-specific. There's no point in the server checking its own FPS and showing it to everyone—that wouldn't tell a player why their screen is freezing.
Here is a basic way to structure the script:
```lua local RunService = game:GetService("RunService") local Stats = game:GetService("Stats") local players = game:GetService("Players")
local player = players.LocalPlayer local gui = script.Parent -- Assuming the script is inside the GUI local fpsLabel = gui:WaitForChild("FPSLabel") local pingLabel = gui:WaitForChild("PingLabel") local memLabel = gui:WaitForChild("MemLabel")
local lastUpdate = 0 local frameCount = 0
RunService.RenderStepped:Connect(function(deltaTime) frameCount = frameCount + 1 lastUpdate = lastUpdate + deltaTime
-- We only update the text every second so it's readable if lastUpdate >= 1 then local fps = math.floor(frameCount / lastUpdate) fpsLabel.Text = "FPS: " .. fps -- Reset counters frameCount = 0 lastUpdate = 0 -- Get Ping (Round Trip Latency) local ping = math.floor(player:GetNetworkPing() * 1000) pingLabel.Text = "Ping: " .. ping .. "ms" -- Get Memory Usage in MB local mem = math.floor(Stats:GetTotalMemoryUsageMb()) memLabel.Text = "Mem: " .. mem .. "MB" end end) ```
This script is pretty lightweight. It uses RenderStepped, which fires every single time the game renders a frame. However, we aren't updating the text 60 times a second. That would be a jittery mess and actually hurt performance. Instead, we count the frames and update the display once per second. It's much easier on the eyes.
Making the stats look "Pro"
If you want to go the extra mile, you can make the colors change based on the performance. It's a nice visual cue for the player. For example, if the FPS is above 55, keep the text green. If it drops below 30, turn it red.
It's a small touch, but it makes the tool feel way more integrated into the game. You could do the same for ping—under 100ms is green, over 300ms is "maybe check your router" red.
Don't let your script become the problem
The irony of a roblox performance stats script is that if you write it poorly, it can actually cause the lag you're trying to monitor. I've seen scripts that try to calculate complex averages every single frame or use wait() in a way that creates weird threading issues.
Always use RunService for anything involving frame rates. It's synced with the engine's heartbeat. Also, avoid using Instance.new or heavy string manipulation inside the loop. Keep it simple: get the number, round it, and shove it into the text property.
Testing on different devices
Once you've got your script running, don't just assume it works because it looks good in Roblox Studio. Studio performance is notoriously different from the actual game client. Publish the game and play it on a phone or an old laptop.
Check if the memory usage stays stable. If you notice the "Mem" count going up by 1MB every minute while you're just standing still, you've likely got a script that's creating tables or objects without cleaning them up. This is why the script is so valuable—it catches the "slow deaths" of servers that you wouldn't notice in a five-minute test session.
Taking it a step further
If you're managing a massive project, you might even want to send this data back to a server-side log or an external analytics tool. Imagine being able to see that 80% of your players are running at less than 20 FPS. That's a huge red flag that your map is too detailed or your code is too heavy.
But for most of us, a simple on-screen display is plenty. It gives you the "ground truth" of how the game is behaving. You don't have to wonder if the game feels sluggish; you can just look at the corner of your screen and know for sure.
Anyway, it's a quick project that pays off almost immediately. Once you have a reliable roblox performance stats script in your toolbox, you'll probably end up dropping it into every single game you make. It's just one of those essential pieces of kit that makes the whole development process a lot less stressful. Happy dev-ing!