Quick Summary (TL;DR):The SGP40 and SGP41 are Sensirion metal-oxide gas sensors designed for indoor-air-quality monitoring with ESP32, ESPHome and Home Assistant. The biggest difference is simple: SGP40 measures VOC behaviour only, while SGP41 adds a second sensing pixel for oxidizing…
Quick Summary (TL;DR):If the project is specifically about measuring temperature and relative humidity as accurately as possible, the SHT45 is the clear winner: Sensirion specifies approximately ±1.0% RH and ±0.1°C typical accuracy, very low long-term drift, a fast digital I²C…
For most ESP32 and Home Assistant projects, the SHT40 remains the best-value choice. The SHT41 is essentially a tighter-tolerance SHT40: both have the same typical ±1.8% RH and ±0.2°C accuracy, but the SHT41 guarantees substantially better worst-case humidity accuracy across…
Choose the BME280 if you only need reliable temperature, humidity and barometric pressure — it is simple, extremely low power and still one of the best choices for ESP32 weather stations and battery sensors. Choose the BME688 for a new…
This project turns an ESP32 into a simple learning IR remote. An IR receiver captures a button press from a TV, amplifier, fan or other infrared remote, the ESP32 identifies the protocol, address and command, stores the code in memory,…
The Ai-Thinker RD-03D is a 24 GHz FMCW mmWave radar designed for multi-target trajectory tracking. Connected to an ESP32, ESPHome can report up to three targets simultaneously, including each target’s X/Y position, distance, speed and angle, then expose everything directly…
The HLK-LD2420 is a 24 GHz mmWave presence sensor that works very well with an ESP32 and Home Assistant through ESPHome. Unlike a PIR sensor, it can maintain presence from both movement and smaller stationary-body movements. ESPHome provides native LD2420…
For most new ESP32 and Home Assistant projects, the SCD41 is the best overall CO₂ sensor because it combines a tiny package with better accuracy than the SCD40, a specified range up to 5,000 ppm, and low-power single-shot measurement. The…
For most new ESP32 and Home Assistant projects, the SHT40 is the best value: it is newer, smaller, faster, and consumes less power than the SHT31 while offering slightly better humidity accuracy. Choose the SHT45 when measurement accuracy matters most…
For most Home Assistant rooms, the LD2410 is still the best all-round mmWave presence sensor because it is inexpensive, mature, highly configurable and particularly good at detecting a person who is sitting or barely moving. Choose the LD2450 when you…