Build a Smart Letterbox Notifier with Arduino & OLED — Never Miss Mail Again

Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.

If you've ever come home to a pile of mail and wished you knew exactly how many items arrived, this project turns that idea into reality. The kit uses a simple yet robust infrared break beam sensor array that counts letters and small parcels as they drop through the letterbox slot. An OLED display mounted discreetly shows the live unread count—making it perfect for busy households, home offices, or hostel mailrooms.

What You'll Build

You'll assemble a self-contained module that sits inside any standard letterbox. Each time a letter passes through the invisible IR beam, the Arduino increments an internal counter and updates the clear 0.96-inch OLED screen. With the included DS3231 real-time clock, you can optionally log timestamps, turning the project into a data logger for full mail tracking. The result is a reliable, low-power device that gives you instant mail awareness every time you walk by the door.

What You'll Learn

• How to set up an IR break beam circuit using an emitter, photodiode, and comparator for clean digital output
• Interfacing a 0.96-inch OLED display over I2C with Arduino for crisp, real-time readouts
• Integrating a DS3231 real-time clock to maintain accurate time stamps, even after power loss
• Writing debouncing and counting logic to filter out false triggers from slow-moving objects

Kit Contents

Why Buy This Kit Instead of Sourcing Parts Separately

Who This Kit Is For

This intermediate kit is designed for CBSE Class 12 students building a prototype for physics or computer science practicals, B.Tech ECE/EEE students working on mini projects or Smart India Hackathon ideas, and ATL Tinkering Lab mentors guiding sensor-based innovation. It’s also a natural next step for hobbyists who have completed basic Arduino tutorials and want to apply sensing, display, and real-time clock integration in a real-world scenario.

Built and Backed by Compoden

Every Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.