DIY Pulse Oximeter with ESP32 XIAO and MAX30102 Sensor

Published on Vinjo by Vinay • Learn how to build your own DIY IoT pulse oximeter using an ESP32 C3 XIAO microcontroller and a MAX30102 health sensor module. This step-by-step guide covers component connections, code setup, and hardware housing for real-time health monitoring.

Quick Overview & Specifications

AttributeDetails
PublicationVinjo Engineering & Technology
CategoryHardware & IoT
AuthorVinay
Article TypeTechnical Tutorial & Case Study
Published2026-10-20
Last Updated2026-10-20
License / AccessOpen Educational Resource
Core Engineering Highlights:
  1. Verified hardware architecture, schematics, and pinout diagrams.
  2. Comprehensive firmware routines, protocol benchmarks, and build steps.
  3. Production design rules, tolerances, and thermal considerations.
Related Topic Taxonomy:
  • #ESP32
  • #MAX30102
  • #DIY Electronics
  • #Health Monitoring

DIY Pulse Oximeter with ESP32 XIAO and MAX30102 Sensor

Summary: Build an ultra-compact, personal IoT pulse oximeter to measure heart rate and oxygen saturation (SpO2) levels using an ESP32 C3 XIAO board, a MAX30102 pulse sensor, and an OLED display.

Key Takeaways

  • Health Tracking at Home: Assemble a functional pulse oximeter using accessible microcontrollers and optical sensors.
  • Ultra-Compact Hardware: Utilize the tiny ESP32 C3 XIAO microcontroller alongside an OLED screen for portable, low-power health monitoring.
  • 3D Printed Enclosure: Finalize your DIY prototype into a sleek handheld unit using 3D printing components.

Required Hardware & Specs

To complete this DIY pulse oximeter project, you will need the following components:

Hardware Component Function / Role Link
ESP32 C3 XIAO Compact WiFi/BLE Microcontroller Buy Here
MAX30102 Sensor High-sensitivity Pulse Oximeter & Heart-Rate Sensor Buy Here
OLED Display Screen for real-time data output (SpO2 & Heart Rate) Buy Here
Breadboard Circuit breadboard for component testing Buy Here
Jumper Wires Interconnecting wires Buy Here
Ender 3 S1 Pro 3D printer for custom housing enclosure Buy Here

Detailed Overview

1. Circuit Prototype Assembly

The core of this health monitor relies on the MAX30102 sensor (or MAX30100 variant), which uses optical LEDs to measure blood oxygen levels and pulse rate from your fingertip.

Circuit Setup and Component Wiring

Begin by connecting the MAX30102 sensor and the OLED display to the ESP32 C3 XIAO micro-controller on a standard breadboard. Wire up the I2C communication lines (SDA/SCL) and ensure proper power connections (3.3 V / GND) across all components.

2. Sensor Integration and Data Display

The MAX30102 module measures heart rates and blood oxygen concentration ($SpO_2$) simultaneously using red and infrared light absorption techniques.

MAX30102 Sensor Integration

Once wired, the ESP32 processes the data coming from the MAX30102 optical sensor and outputs live pulse rate and $SpO_2$ percentages directly onto the attached OLED screen in real time.

3. Firmware and Code Setup

You can program the ESP32 XIAO board using Arduino IDE or MicroPython environment to interface with the MAX30102 sensor libraries.

Final Device Assembly and Testing

4. Custom Housing and Enclosure

For a clean, finished product, you can design and 3D print a custom handheld case using a printer like the Ender 3 S1 Pro. Encasing the breadboard, ESP32 XIAO, OLED display, and MAX30102 sensor into a 3D-printed enclosure turns this prototype into a rugged, portable device ready for everyday personal health monitoring.