Finding a reliable roblox anti exploit script is basically the first thing most developers do once their game starts getting some actual players. It's a bit of a rite of passage, honestly. You spend weeks building this awesome world, tuning the mechanics, and getting the lighting just right, only for some kid to join and start flying around at Mach 10, ruining the experience for everyone else. It's frustrating, but it's just the reality of developing on a platform as huge as Roblox.
If you've spent any time in the DevForum or scrolling through scripting tutorials, you've probably realized that there isn't one single "magic" script you can just drop into your game to stop every cheater forever. It doesn't work like that. Exploiting is a constant cat-and-mouse game. However, you can make it so difficult for them that they eventually give up and go bother someone else's game instead.
Why You Can't Trust the Client
The biggest mistake I see new developers make is putting their roblox anti exploit script inside a LocalScript. I get why—it feels easier to check things on the player's side. But here's the thing: the "client" is the player's computer, and they have total control over it. If you put a script on their machine that says "don't walk too fast," they can just delete that script or tell it to stop running.
To actually protect your game, you have to think server-side. The server is the "truth." If the server thinks a player is standing at point A, but the player's computer says they are at point B (halfway across the map), the server should be the one to decide what's real. This is the foundation of any decent security setup. If it isn't happening on the server, it might as well not be happening at all.
Movement and Physics Checks
Most exploiters start with the basics: speed hacks, fly hacks, and teleporting. These are the most "visual" cheats and they're incredibly annoying for other players. Luckily, they're also some of the easiest to catch if you're smart about your roblox anti exploit script logic.
Calculating Magnitude
The most common way to catch a speed hacker is to check their Magnitude. Every second or so, your script should look at where the player was and where they are now. If the distance between those two points is way higher than their WalkSpeed should allow, you've got a problem.
But you have to be careful here. If a player has a high ping or their game stutters, they might "snap" forward, making the server think they traveled 50 studs in a millisecond. If your script is too aggressive, you'll end up kicking innocent people who just have bad internet. A good way to handle this is by using a "violation" system. Don't kick them the first time it happens; just teleport them back to their last known good position. If it happens five times in a row? Then you might want to pull the trigger on a kick.
Checking for Flight
Flight is a bit trickier because players jump, fall, and use tools. A simple way to check for a fly hack is to cast a ray downwards from the character's root part. If they've been "in the air" for ten seconds straight but aren't falling (their Y-velocity is zero or positive), they're probably flying. Again, you have to account for things like parachutes, vehicles, or special abilities you've added to your game.
The Nightmare of Remote Events
If movement hacks are the most visible, Remote Event abuse is the most dangerous. This is where a roblox anti exploit script really earns its keep. RemoteEvents are how the client talks to the server. For example, when a player clicks a "Buy" button, a RemoteEvent tells the server, "Hey, I want to buy this sword."
Exploiters love to spam these. If you haven't secured your remotes, an exploiter can fire that "Buy" event a thousand times a second, or they might change the arguments. Instead of sending the ID for a $50 sword, they might try to send an ID for a $0 item, or even try to pass a negative number to see if your script adds money to their account instead of taking it away.
Always Validate Everything
Never, ever trust the data coming through a RemoteEvent. If a player fires a remote to damage an enemy, don't just take their word for it. Check on the server: 1. Is the player close enough to the enemy to actually hit them? 2. Does the player even have a weapon equipped? 3. Has enough time passed since their last attack (cooldown check)?
If any of those answers is "no," just ignore the request. You don't even necessarily need to kick them; just don't let the action happen.
Why "Off-the-Shelf" Anti-Exploits Fail
You'll find plenty of free roblox anti exploit script models in the Toolbox. Some of them are actually decent, like Adonis or some of the community-made "Simple Anticheats." They're great for catching the really low-level stuff, like people trying to use basic cheat engines or common scripts.
The problem is that the people making the exploits also have access to these free models. They download them, see exactly how they work, and then write a "bypass" specifically for them. If your game becomes popular, exploiters will specifically target your game's unique mechanics. This is why a custom-built solution is usually better in the long run. It doesn't have to be complex, but it needs to be specific to how your game works.
Handling the Performance Impact
One thing people forget when writing a roblox anti exploit script is that these checks take up resources. If you have a server with 50 players and you're running 10 different math-heavy checks on every single player every single frame, your server is going to lag. And when the server lags, the game feels bad for everyone, which is exactly what you were trying to prevent in the first place.
Keep your checks efficient. You don't need to check for speed hacks every frame. Once every second is usually plenty. You also don't need to check every player at the exact same millisecond. You can stagger the checks so the server's workload is spread out.
Dealing with False Positives
There is nothing that kills a game's reputation faster than a "ban wave" that hits a bunch of innocent players. It's a nightmare. If your roblox anti exploit script is too sensitive, you'll lose your player base.
Always lean on the side of caution. Instead of an immediate permaban, use temporary kicks or just "rubber-banding" (teleporting them back). If someone is truly exploiting, they'll keep triggering the checks, and eventually, the evidence will be undeniable. If it's just a kid with a laggy laptop, they'll get snapped back a few times, which is annoying, but at least they can still play the game.
Final Thoughts on Security
Building a roblox anti exploit script isn't a "set it and forget it" kind of task. As you update your game and add new features, you'll likely open up new holes that exploiters will find. The best thing you can do is stay involved with your community. If players start reporting a specific type of cheating, look into your RemoteEvents and movement logic to see where the gap is.
At the end of the day, you probably won't stop 100% of exploiters. There's always someone with too much time on their hands who will find a way around things. But by covering the basics—securing your remotes, checking movement on the server, and validating player actions—you'll stop 95% of the "script kiddies" who are just using someone else's copy-pasted cheats. That's usually more than enough to keep your game fun and fair for the people who actually want to play it.