nRF52 vs ESP32 for BLE and IoT products
Which chip fits your device, based on power, wireless, processing and battery life.
Short answer: choose an nRF52 (nRF52832 or nRF52840) for battery-powered Bluetooth Low Energy products such as wearables, trackers and sensors that must run for months on a small battery. Choose an ESP32 when the device needs Wi-Fi, a camera or more processing power and has USB or mains power. Many products use both: an nRF52 sensor talking to an ESP32 gateway.
Side-by-side comparison
| nRF52 (nRF52832 / nRF52840) | ESP32 family (ESP32, S3, C3, C6) | |
|---|---|---|
| Core | Arm Cortex-M4F at 64 MHz | Xtensa (ESP32, S3) or RISC-V (C3, C6), up to 240 MHz, dual core on ESP32 and S3 |
| Wireless | Bluetooth LE; nRF52840 adds Bluetooth 5 long range, Thread and Zigbee | Wi-Fi plus Bluetooth LE; C6 adds Wi-Fi 6, Thread and Zigbee |
| Radio current | Around 5 mA when transmitting or receiving | Wi-Fi transmit peaks reach a few hundred mA |
| Deepest sleep | Under 1 µA in System OFF | Around 10 µA in deep sleep on the original ESP32 |
| Memory | Up to 1 MB flash and 256 KB RAM (nRF52840) | Around 400–520 KB RAM, external flash and optional PSRAM |
| SDK | nRF Connect SDK, built on Zephyr | ESP-IDF, built on FreeRTOS |
| Best at | Coin-cell and small-battery BLE devices | Connected devices with Wi-Fi, cameras, displays and local processing |
Figures are typical datasheet values; real battery life depends on how often the radio wakes and what the sensors draw. Always measure on your own board.
When nRF52 is the better choice
- The device runs on a coin cell or small Li-Po battery and must last weeks or months.
- It talks to a phone app over Bluetooth rather than to a router.
- It is small: rings, bands, insoles, tags and medical-style sensors.
- You want certified modules (for example from u-blox or Raytac) to shorten radio certification.
Our smart shoe sensing platform uses an nRF52832-based module for exactly this reason, and the ultra-slim BLE healthband follows the same low-power pattern.
When ESP32 is the better choice
- The device must reach the internet directly over Wi-Fi.
- It handles images, audio or a display. The ESP32-S3 adds vector instructions for small on-device AI models.
- It is powered from USB or mains, so a few hundred milliamps during Wi-Fi bursts is acceptable.
- You want one low-cost chip for Wi-Fi, Bluetooth and the application.
See our ESP32 embedded vision project and home automation controller for typical ESP32 designs.
Using both in one product
A common architecture is battery-powered nRF52 sensors that send data over Bluetooth to a mains-powered ESP32 hub, which then forwards it over Wi-Fi to the cloud. Each chip does what it is best at, and the battery devices stay small and long-lived.
Firmware and update considerations
Plan over-the-air updates from day one. On nRF52 this usually means MCUboot through the nRF Connect SDK; on ESP32 it means ESP-IDF's dual-partition OTA. Our guide to fail-safe OTA firmware updates covers the rollback design for both.
Frequently asked questions
Is nRF52 better than ESP32 for battery life?
For Bluetooth-only devices, yes. nRF52 radios draw around 5 mA and sleep below 1 µA, which suits coin-cell products. ESP32 Wi-Fi bursts draw far more.
Does nRF52 have Wi-Fi?
No. nRF52 chips support Bluetooth LE, and the nRF52840 also supports Thread and Zigbee. For Wi-Fi you need a separate chip such as an ESP32 or Nordic's nRF70 series.
Which ESP32 should I use for a BLE product?
If you also need Wi-Fi, the ESP32-C3 or ESP32-S3 are common choices. For Bluetooth-only, battery-powered designs an nRF52 is usually more efficient.
Can SixSol develop firmware for both?
Yes. We build firmware on nRF Connect SDK and ESP-IDF, including Bluetooth, sensor drivers, low-power modes and OTA updates.