A roblox custom gui filter script is one of those things you don't realize you need until you're halfway through building a cool new feature and realize Roblox might take your game down if you skip it. Whether you're making a custom chat system, a name tag editor, or a billboard that lets players leave messages, you've got to make sure that text is filtered. Roblox is huge on safety, and they don't play around when it comes to keeping the platform clean for younger audiences. If you're letting players input text and show it to others without a filter, you're basically asking for a moderation headache.
The good news is that you don't have to write a list of "bad words" yourself. In fact, you shouldn't. Roblox has its own built-in systems to handle the heavy lifting, but connecting your custom GUI to those systems can be a bit of a puzzle if you haven't done it before. Let's break down how to set this up so your game stays compliant and your players stay safe.
Why Filtering Actually Matters
Before we dive into the code, let's talk about why we're doing this. It's not just about stopping people from saying things they shouldn't. It's about how Roblox operates as a platform. Because there are so many kids on the site, the "Filter" is dynamic. It changes based on the age of the player seeing the text. A 13+ player might see something that gets hashtagged out for an under-13 player.
If you try to make your own filter with a simple "find and replace" script, you're going to fail. You'll miss variations, slang, and a million other things that Roblox's AI is already trained to catch. Plus, using the official TextService is a requirement. If a moderator checks your game and sees you're bypassing the official filter, they can (and will) shut it down.
The Foundation: TextService and RemoteEvents
To get a roblox custom gui filter script working, you need to understand one big rule: Filtering must happen on the server.
You can't just filter the text inside the player's LocalScript. Well, technically you could try, but the results wouldn't be secure, and the methods required only work on the server side anyway. This means we need a bridge between the player's screen (the Client) and the game's logic (the Server). This bridge is a RemoteEvent.
Here is the general flow of how it works: 1. The player types something into your TextBox. 2. They hit a "Submit" button. 3. A LocalScript fires a RemoteEvent, sending that text to the server. 4. A Script on the server receives the text and asks Roblox's TextService to filter it. 5. The server then takes that filtered text and does whatever it needs to do (like showing it on a wall or sending it to other players).
Setting Up Your GUI
First, let's assume you've got a basic GUI. You probably have a ScreenGui in StarterGui, and inside that, a Frame with a TextBox for input and a TextButton to send the message.
Make sure your TextBox is named something clear, like InputBox. Once that's ready, you'll need to create a RemoteEvent in ReplicatedStorage. Let's name it FilterRequest. This event is what allows the player to say, "Hey server, I want to say this, please check it for me."
Writing the LocalScript
In your TextButton, you'll want a LocalScript. This script is pretty simple. It just listens for the click and sends the data over the fence.
```lua local button = script.Parent local inputBox = button.Parent:WaitForChild("InputBox") local replicatedStorage = game:GetService("ReplicatedStorage") local filterEvent = replicatedStorage:WaitForChild("FilterRequest")
button.MouseButton1Click:Connect(function() local textToSend = inputBox.Text if textToSend ~= "" then filterEvent:FireServer(textToSend) inputBox.Text = "" -- Clear the box after sending end end) ```
This is the "client-side" of your roblox custom gui filter script. It's not doing any filtering yet; it's just the delivery boy.
The Heavy Lifting: The Server Script
Now, let's go to ServerScriptService and create a regular Script. This is where the magic (and the rules) live. We need to use TextService:FilterStringAsync().
One thing that trips people up is that this function can fail. If Roblox's filtering servers are down or having a hiccup, the script will error out. Because of that, we always wrap it in a pcall (protected call) to make sure our whole game doesn't crash just because the filter is being moody.
```lua local TextService = game:GetService("TextService") local ReplicatedStorage = game:GetService("ReplicatedStorage") local filterEvent = ReplicatedStorage:WaitForChild("FilterRequest")
filterEvent.OnServerEvent:Connect(function(player, rawText) if rawText == "" then return end
local filteredText = "" local success, errorMessage = pcall(function() -- This gets the filter object local filterResult = TextService:FilterStringAsync(rawText, player.UserId) -- This converts it to a string safe for everyone filteredText = filterResult:GetNonChatStringForBroadcastAsync() end) if success then print("Filtered text: " .. filteredText) -- Now you can send this text to other players or put it on a GUI else warn("Error filtering text: " .. errorMessage) end end) ```
Understanding GetNonChatStringForBroadcastAsync
In the code above, I used a method called GetNonChatStringForBroadcastAsync(). This is the most common way to handle a roblox custom gui filter script if you want the text to be seen by every single person in the server.
Roblox has different levels of filtering. If you're making a one-on-one private messaging system, you'd use GetChatStringForUserAsync(). But for most custom GUIs—like a sign or a global announcement—"Broadcast" is what you want. It applies the strictest filtering so that even the youngest players can safely see the message.
Common Mistakes to Avoid
When you're setting up your roblox custom gui filter script, it's easy to get frustrated. One big mistake is forgetting that FilterStringAsync requires the UserId of the player who sent the message. Roblox uses this to track who is saying what, which helps their internal moderation systems.
Another mistake is trying to call the filter too often. If you have a script that tries to filter text every single time a player presses a key, you're going to hit "rate limits." Basically, Roblox will tell you to slow down, and your filter will stop working. Only fire the filter when the player "submits" their text.
Testing Your Filter
Here's a weird quirk: filtering doesn't always show up in Roblox Studio. When you're testing your game by yourself in the editor, you might see the raw "bad" words show up in the output. Don't panic! Roblox often disables the actual hashtagging in Studio for the developer.
To really see if your roblox custom gui filter script is working, you should publish the game and join it on a real Roblox client. If you type something that should be filtered and it comes out as ####, then you know you've done it right.
Handling the Output
Once you have that filteredText variable on the server, you need to show it to the players. Usually, you'd use another RemoteEvent to fire back to all the clients, or you'd update a StringValue that is set to a SurfaceGui.
Whatever you do, just make sure that the text that ends up on the screen is the filtered version, not the original rawText that the player sent. If you accidentally use the raw version, the filter was pointless!
Wrapping Up
Building a roblox custom gui filter script might feel like an annoying extra step when you just want to get to the fun parts of game design, but it's a foundational skill for any Roblox dev. It keeps your community healthy and ensures your hard work doesn't get deleted for a ToS violation.
Just remember: keep it on the server, wrap it in a pcall, and always use the official TextService. Once you get the hang of it, you can reuse the same logic for every game you make. It's one of those "set it and forget it" pieces of code that makes your game feel much more professional. Happy scripting!