NUI Introduction

This guide walks through NUI Introduction from preparation through verification, with a rollback path and the checks that matter in a real fivem servers environment.

How NUI fits together

A typical NUI resource has an fxmanifest.lua, client/server code where needed, and web assets such as HTML/CSS/JS. The manifest declares ui_page and the files clients need.

Minimal manifest shape

fx_version 'cerulean'
game 'gta5'
ui_page 'web/index.html'
files { 'web/index.html', 'web/style.css', 'web/app.js' }
client_script 'client.lua'

Opening and closing

Your Lua/JS client code controls focus and messages. Always provide a reliable close path; a stuck focus state can make the player appear frozen.

Callbacks

Treat data coming from the browser UI as untrusted input. If a callback ultimately changes authoritative game/server state, validate the action again on the server.

Debugging

Use the FiveM/client console and NUI developer tooling where available. Check file paths, manifest files, browser-console errors, callback names and focus state.

Document status

Last reviewed: September 2026
Version note: Use the instructions that match your installed product/resource version. When behavior differs from your release, check its release notes before changing production configuration.