How to Build an ESP32 RFID Attendance System | Google Sheets Logger Tutorial (MFRC522 + OLED)

Build a complete ESP32 RFID Attendance System that logs every scan directly to Google Sheets — no server, no database, no hosting required. This tutorial covers wiring, code, OLED UI setup, Google Apps Script, HTTPS requests, and real-time logging. Perfect for schools, shops, offices, labs, DIY projects, and IoT automation. ✅ WHAT YOU WILL LEARN • ESP32 + RC522 RFID wiring • SH1106/SSD1306 OLED setup (I²C) • How to read RFID tags (UIDs) • Create a Google Sheets API using Apps Script • Send secure HTTPS GET/POST requests • Log Entry/Exit with timestamps • Organize attendance data automatically • Debug common RFID, WiFi & HTTPS issues ✅ FEATURES OF THIS PROJECT ✔ Real-time RFID logging ✔ Clean OLED UI ✔ No backend server ✔ Entry & Exit system ✔ Unlimited RFID cards ✔ Secure HTTPS communication ✔ Beginner-friendly ✔ Expandable (buzzer, relay, door lock, ESP32-CAM, dashboard) ✅ DOWNLOAD PROJECT FILES • Full Arduino Code • Wiring Diagram (PDF) • Google Apps Script 🔗 Download Here: https://drive.google.com/drive/folder... ✅ CHAPTERS 00:00 — Demo 00:40 — Components 01:20 — Wiring Overview 03:10 — Google Sheets Setup 06:00 — Sending Test Data 08:40 — RFID Reading Code 10:20 — Logging to Cloud 12:40 — Final Demo ✅ ADVANCED UPGRADES • Add a buzzer • Add a relay for door access • Add fingerprint sensor • Add ESP32-CAM face recognition • Build a Google Data Studio dashboard • Build a mobile app to view logs ✅ TROUBLESHOOTING RFID not detecting → increase antenna distance OLED blank → verify SDA/SCL pins Sheet not updating → check Web App deployment HTTPS errors → verify URL format WiFi drops → enable auto-reconnect 🎵 **MUSIC Track: Ascence - About You [NCS Release] Music provided by NoCopyrightSounds. Watch: [https://NCS.lnk.to/YouTubeAT](https://NCS.lnk.to/YouTubeAT) Free Download / Stream: [https://ncs.io/AboutYou](https://ncs.io/AboutYou) Track: Lost Sky - Vision [NCS Release] Music provided by NoCopyrightSounds. Watch: [   • Video  ](   • Video  ) Free Download / Stream: [http://ncs.io/VisionID](http://ncs.io/VisionID) Track: Y&V - Lune [NCS Release] Music provided by NoCopyrightSounds. Watch: [   • Y&V - Lune | Electronic | NCS - Copyright ...  ](   • Y&V - Lune | Electronic | NCS - Copyright ...  ) Free Download / Stream: [http://ncs.io/lune](http://ncs.io/lune) #ESP32 #RFID #IoT #GoogleSheets #AttendanceSystem #MakerProject #Arduino #SH1106 #MFRC522 #Tutorial #DIY #Coding #Electronics