🌟 Why This Matters

You built a website. Users sign up with Google. Firebase Auth stores them securely.

But… you can’t see them — especially if you have 1000+ users.

Firebase Auth API returns max 1000 users per call. Without pagination, you miss data.

This workflow:

• ✅ Fetches ALL users (even 10,000+)
• ✅ Automatically paginates through results
• ✅ Upserts into Google Sheets (no duplicates)
• ✅ Runs daily, automatically

All in n8n — no code, no backend.

🧰 What You’ll Build

1. ✅ Schedule Trigger → Runs daily at midnight
2. ✅ Initialize State → Prepares pageToken, allUsers[]
3. ✅ HTTP Request → Fetches 1000 users per page from Firebase Auth API
4. ✅ Merge & Check Pagination → Merges current page + checks if more pages exist
5. ✅ Loop Back → If hasMore = true, fetch next page
6. ✅ Format Final Data → Clean, readable columns
7. ✅ Google Sheets → Upsert by Email (no duplicates!)

📦 Tools You Need

🧭 STEP-BY-STEP: UPDATED WORKFLOW

All nodes are connected in order. Execute each step to test.

✅ STEP 0: One-Time Setup

A. Create Your Google Sheet

1. Go to sheets.google.com
2. Create a new sheet → Name it: Firebase Auth Users
3. In Row 1, add headers:

   exportedAt | uid | email | displayName | phoneNumber | emailVerified | disabled | createdAt | lastLoginAt

4. Click Share → Get shareable link → Set to “Anyone with link can edit” (for testing)

B. Set Up n8n Credentials

1. Go to n8n.cloud → Sign up (free)
2. Go to Credentials → Add Credential
3. Add “Google Service Account API”
• Credential Type: Firebase Admin SDK
• Paste your Firebase Service Account JSON (from Console → Project Settings → Service Accounts)
• Save as: Firebase Auth API
4. Add Google Sheets OAuth → Connect your Google Account → Allow access

🧩 STEP 1: Build the Workflow

➤ NODE 1: Schedule Trigger (Run Daily)

• Add “Cron” node
• Mode: Every Day
• Timezone: Asia/Kolkata (or your timezone)
• Time: 00:05
• Name: Daily Trigger

➤ NODE 2: Function → Initialize Pagination State

• Add “Function” node → Connect from Cron
• Name: Initialize State

return [{
  json: {
    pageToken: null,        // Start from first page
    allUsers: [],           // Empty array to accumulate users
    project_id: "fir-fb08a" // ← REPLACE WITH YOUR PROJECT ID
  }
}];

➤ NODE 3: HTTP Request → Fetch Users (Paginated)

• Add “HTTP Request” node → Connect from Function
• Name: Fetch Auth Users Page
• Method: POST
• URL: https://identitytoolkit.googleapis.com/v1/projects/{{$json.project_id}}/accounts:query
• Authentication: Predefined Credential Type
• Credential Type: Google Service Account API
• Credential: Firebase Auth API

Headers:

Body (JSON):

{
  "maxResults": 1000,
  {{ $json.pageToken ? '"pageToken": "' + $json.pageToken + '",' : '' }}
  "returnUserInfo": true
}

➤ NODE 4: Function → Merge Users + Check Pagination

• Add “Function” node → Connect from HTTP Request
• Name: Merge Users & Check Next Page

const newUsers = $input.item.json.users || [];
const existingUsers = $input.item.json.allUsers || [];
const mergedUsers = [...existingUsers, ...newUsers];
const nextPageToken = $input.item.json.nextPageToken || null;
const hasMore = !!nextPageToken;

return {
  ...$input.item.json,
  allUsers: mergedUsers,
  pageToken: nextPageToken,
  hasMore: hasMore
};

➤ NODE 5: IF → Check if More Pages Exist

• Add “IF” node → Connect from Function
• Name: More Pages?
• Condition:
  • Value 1: hasMore
  • Operation: is equal to
  • Value 2: true

➤ NODE 6: Function → Format Final User Data

• Add “Function” node → Connect from IF → FALSE
• Name: Format Users for Sheets

return ($input.item.json.allUsers || []).map(user => ({
  exportedAt: new Date().toISOString(),
  uid: user.localId,
  email: user.email || '',
  displayName: user.displayName || '',
  phoneNumber: user.phoneNumber || '',
  emailVerified: user.emailVerified ? 'Yes' : 'No',
  disabled: user.disabled ? 'Yes' : 'No',
  createdAt: user.createdAt ? new Date(parseInt(user.createdAt)).toISOString() : '',
  lastLoginAt: user.lastLoginAt ? new Date(parseInt(user.lastLoginAt)).toISOString() : ''
}));

➤ NODE 7: Google Sheets → Upsert by Email

• Add “Google Sheets” node → Connect from Function
• Operation: Append or Update Row
• Document: By ID → Paste your Sheet ID (from URL)
• Sheet Name: Select your sheet (e.g., Firebase Auth Users)
• Mapping Column Mode: Map Automatically
• Column to Match On: email ← Prevents duplicates!
• Credentials: Your Google Sheets OAuth credential

🧠 PRO TIPS & BEST PRACTICES

➤ Handle Rate Limits

Add a “Wait” node (1-2 sec) between page fetches if you hit rate limits.

➤ Add Error Handling

Use “Catch” node → log failed pages to another sheet.

➤ Schedule Weekly for Large Datasets

If you have 50k+ users, run weekly to avoid timeouts.

➤ Add “Last Sync” Column

In Sheet → add column → ={{ $now }} → track when sync ran.

🚫 COMMON ERRORS & FIXES

💬 FINAL THOUGHTS

You just built an enterprise-grade, scalable, no-code user sync system.

Handles pagination. Prevents duplicates. Runs automatically.

No developers. No budget. No headaches.

Just you, n8n, and automation.

🚀 “Automate the boring stuff — focus on what matters.”