How to Connect a Flutter Project to Firebase (Step-by-Step Guide)

By the end of this guide your Flutter app will be connected to Firebase on Android, iOS and web, using the official FlutterFire CLI. No manual copying of config files, no guessing.

Firebase is Google's backend platform. Once your app is connected, you can add login (Firebase Authentication), a real-time database (Cloud Firestore), file uploads (Cloud Storage), push notifications and more, without writing your own server.

This guide is written for beginners. It works on Windows and macOS, and takes about 20 minutes.

In this post you will learn:

• What you need before you start
• How to create a Firebase project
• How to install the Firebase CLI and the FlutterFire CLI
• How to run flutterfire configure and what it creates
• How to initialize Firebase in main.dart
• How to check that the connection works
• How to fix the most common errors

Before you start: what you need

• Flutter installed and working. Run flutter doctor in a terminal. If you have not installed Flutter yet, follow my Flutter installation guide for Windows and macOS first.
• A Flutter project. Use an existing one, or create a new one:

flutter create my_firebase_app
cd my_firebase_app

• A Google account to sign in to the Firebase console.
• Node.js (only for the easiest way of installing the Firebase CLI). Download the LTS version from nodejs.org.

How the connection works (in one minute)

Your Flutter app needs to know which Firebase project to talk to. That information (project ID, API key, app ID and so on) is different for Android, iOS and web.

In the old days you downloaded google-services.json and GoogleService-Info.plist by hand and edited Gradle files. Today the FlutterFire CLI does all of that with one command and writes everything into a single Dart file, lib/firebase_options.dart. Your app reads that file when it starts.

Firebase project  →  flutterfire configure  →  lib/firebase_options.dart  →  Firebase.initializeApp()

Step 1: Create a Firebase project

1. Go to the Firebase console and sign in with your Google account.
2. Click Create a project (or Add project).
3. Enter a project name, for example my-firebase-app. Firebase creates a unique project ID from it.
4. Google Analytics is optional. You can turn it off for a learning project and enable it later.
5. Click Create project and wait until it says your project is ready.

You do not need to click "Add app" for Android or iOS in the console. The FlutterFire CLI will register your apps for you in Step 4.

Step 2: Install the Firebase CLI

The Firebase CLI lets your computer talk to your Firebase account. Open a terminal (Command Prompt or PowerShell on Windows, Terminal on macOS) and run:

npm install -g firebase-tools

If you do not want to install Node.js, you can download the standalone Firebase CLI from the official Firebase CLI docs instead.

Now sign in:

firebase login

A browser window opens. Choose the same Google account you used in the Firebase console and allow access. To confirm it worked, list your projects:

firebase projects:list

You should see the project you created in Step 1.

Step 3: Install the FlutterFire CLI

The FlutterFire CLI is a small Dart tool that connects a Flutter project to Firebase. Install it once on your computer:

dart pub global activate flutterfire_cli

After it installs, test it:

flutterfire --version

If you get "flutterfire: command not found" (or "is not recognized" on Windows), the Dart pub cache folder is not on your PATH. Add it:

• Windows: add %LOCALAPPDATA%\Pub\Cache\bin to your user Path environment variable, then close and reopen the terminal.
• macOS: add this line to ~/.zshrc, then run source ~/.zshrc:

export PATH="$PATH:$HOME/.pub-cache/bin"

Step 4: Run flutterfire configure

Make sure your terminal is inside your Flutter project folder (the one with pubspec.yaml), then run:

flutterfire configure

The CLI asks you a few questions:

1. Select a Firebase project. Use the arrow keys to pick the project from Step 1 and press Enter.
2. Which platforms should your configuration support? Select the platforms you want (Android, iOS, web, macOS, Windows) with the Space bar, then press Enter.
3. It may ask for your Android application ID or iOS bundle ID. It reads them from your project, so the defaults are usually correct.

When it finishes, it has done all of this for you:

• Registered an Android, iOS and/or web app in your Firebase project
• Created lib/firebase_options.dart with the settings for every platform
• Added android/app/google-services.json and ios/Runner/GoogleService-Info.plist where needed
• Added the Google services Gradle plugin to your Android project

Important: run flutterfire configure again whenever you add a new platform, add a new Firebase service that needs config, or change your app's package name or bundle ID. It safely updates the existing files.

Step 5: Add the firebase_core package

firebase_core is the package every other Firebase plugin depends on. Add it from your project folder:

flutter pub add firebase_core

This adds the latest version to the dependencies section of your pubspec.yaml.

Step 6: Initialize Firebase in main.dart

Firebase must be initialized before your app uses any Firebase service. Open lib/main.dart and update the top of the file:

import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';

import 'firebase_options.dart';

Future<void> main() async {
  // Needed because we call native code before runApp().
  WidgetsFlutterBinding.ensureInitialized();

  await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );

  runApp(const MyApp());
}

Three things changed:

• main() is now async and returns Future<void>, so it can await Firebase.
• WidgetsFlutterBinding.ensureInitialized() must be called first. Without it you get a "Binding has not yet been initialized" error.
• DefaultFirebaseOptions.currentPlatform picks the right settings from firebase_options.dart for Android, iOS or web automatically.

Step 7: Check that Firebase is connected

The quickest test is to print the Firebase app name and project ID after initialization. Add this line right after Firebase.initializeApp(...):

debugPrint('Firebase connected: ${Firebase.app().options.projectId}');

Now run the app:

flutter run

In the debug console you should see:

Firebase connected: my-firebase-app

If you see your project ID and the app opens normally, Flutter is connected to Firebase. You can remove the print line now.

Platform-specific settings

Most projects work right away, but older projects sometimes need one of these changes.

Android: minimum SDK version

Recent Firebase versions need Android minSdk 23 or higher. If the build fails with a message about minSdkVersion, open android/app/build.gradle.kts (or build.gradle in older projects) and set it inside defaultConfig:

defaultConfig {
    minSdk = 23
    // ...
}

iOS: deployment target

If pod install fails with a message like "The Firebase pod requires a higher minimum iOS deployment target", open ios/Podfile, uncomment the platform line and set it to the version the error asks for:

platform :ios, '15.0'

Then, from the ios folder, run pod install --repo-update and build again.

Web

Nothing extra is needed. firebase_options.dart already contains your web settings, and Firebase.initializeApp uses them when you run flutter run -d chrome.

Your project after setup

my_firebase_app/
├── android/
│   └── app/
│       └── google-services.json      # added by flutterfire configure
├── ios/
│   └── Runner/
│       └── GoogleService-Info.plist  # added by flutterfire configure
├── lib/
│   ├── firebase_options.dart         # generated, do not edit by hand
│   └── main.dart                     # initializes Firebase
├── firebase.json                     # FlutterFire CLI settings
└── pubspec.yaml                      # firebase_core added here

Is it safe to commit firebase_options.dart to GitHub? Yes, for most apps. The values in it (like the API key) identify your Firebase project; they are not passwords. What protects your data is Firebase Security Rules and App Check, so always set proper rules before you launch.

Common errors and how to fix them

"[core/no-app] No Firebase App '[DEFAULT]' has been created"

You used a Firebase service before calling Firebase.initializeApp(), or forgot to await it. Make sure main() awaits initialization before runApp(), exactly like Step 6.

"flutterfire: command not found"

The pub cache bin folder is not on your PATH. See the fix in Step 3, then open a new terminal window.

"Failed to fetch your Firebase projects" or "Firebase CLI not found"

The FlutterFire CLI uses the Firebase CLI behind the scenes. Run firebase login again, and check that firebase --version works in the same terminal.

"Target of URI doesn't exist: 'firebase_options.dart'"

You have not run flutterfire configure yet, or you ran it in a different folder. Run it from the project root (where pubspec.yaml is).

Android build fails after changing the package name

The package name in Firebase no longer matches your app. Run flutterfire configure again and select Android so a new app is registered with the new package name.

"MissingPluginException" after adding a Firebase package

Hot reload does not load new native plugins. Stop the app completely and run flutter run again. If it still fails, run flutter clean and then flutter pub get.

What to do next

Your app is now connected to Firebase. Every other Firebase feature follows the same pattern: add the package with flutter pub add, enable the service in the Firebase console, and use it in your code.

• Firebase Authentication: let users sign up and log in. Continue with my step-by-step guide: Flutter Firebase Authentication: Login and Sign Up.
• Cloud Firestore: flutter pub add cloud_firestore to save and read data in real time.
• Cloud Storage: flutter pub add firebase_storage to upload images and files.

Keep this checklist for every new project:

1. Create the Firebase project
2. firebase login (once per computer)
3. dart pub global activate flutterfire_cli (once per computer)
4. flutterfire configure
5. flutter pub add firebase_core
6. await Firebase.initializeApp(options: DefaultFirebaseOptions.currentPlatform) in main()