ESP32 is a family of low-cost, energy-efficient microcontrollers that integrate both Wi-Fi and Bluetooth capabilities. These chips feature a variety of processing options, including the Tensilica Xtensa LX6 microprocessor available in both dual-core and single-core variants, the Xtensa LX7 dual-core processor, or a RISC-V microprocessor. In addition, the ESP32 incorporates components essential for wireless data communication such as built-in antenna switches, an RF balun, power amplifiers, low-noise receivers, filters, and power-management modules.
Typically, the ESP32 is embedded on device-specific printed circuit boards or offered as part of development kits that include a variety of GPIO pins and connectors, with configurations varying by model and manufacturer. The ESP32 was designed by Espressif Systems and is manufactured by TSMC using their 40 nm process. It is a successor to the ESP8266 microcontroller.
Since the release of the original ESP32, a number of variants have been introduced and announced. They form the ESP32 family of microcontrollers. These chips have different CPUs and capabilities, but all share the same SDK and are largely code-compatible. Additionally, the original ESP32 was revised (see ESP32 ECO V3, for example).
ESP32 is housed in quad-flat no-leads (QFN) packages of varying sizes with 49 pads. Specifically, 48 connection pads along the sides and one large thermal pad (connected to ground) on the bottom.
The ESP32 system on a chip integrated circuit is packaged in both 6 mm ÃÂ 6 mm and 5 mm ÃÂ 5 mm sized QFN packages.
In 2020, chips ESP32-D0WDQ6 and ESP32-D0WD also got a V3 version (ESP32 ECO V3), which fixes some of the bugs and introduces improvements over the previous versions.
The ESP32 PICO system in package modules combine an ESP32 silicon chip, crystal oscillator, flash memory chip, filter capacitors, and RF matching links into a single 7 mm ÃÂ 7 mm sized QFN package.
The first released PICO was the ESP32-PICO-D4 with 2 CPUs at 240 MHz, 4MiB internal flash, a 40 MHz oscillator and 34 GPIOs.
Later, in 2020, the ESP32-PICO-V3 and ESP32-PICO-V3-02 modules were introduced both based on the ESP32 ECO V3 wafer.
In 2022 the ESP32-S3-PICO-1 module was introduced with USB OTG and internal PSRAM.
ESP32 based surface-mount printed circuit board modules directly contain the ESP32 SoC and are designed to be easily integrated onto other circuit boards. Meandered inverted-F antenna designs are used for the PCB trace antennas on the modules listed below. In addition to flash memory, some modules include pseudostatic RAM (pSRAM).
Development and break-out boards extend wiring and may add functionality, often building upon ESP32 module boards and making them easier to use for development purposes, especially with breadboards.
â ESP32 SoC incorporated directly onto development board; no module board used.
Programming languages, frameworks, platforms, and environments used for ESP32 programming:
Commercial, industrial and academic uses of ESP32:
In March 2025, researchers from Tarlogic Security identified undocumented Host Controller Interface (HCI) commands in the ESP32 Bluetooth firmware, prompting discussions about their functionality and potential implications. This discovery was presented on March 6, 2025, at the RootedCON conference by the Tarlogic Security team.
The identified commands, such as Write Memory (0xFC02), are vendor-specific HCI commands used primarily for debugging and testing purposes. These types of commands are common in Bluetooth controller implementations to assist with development and troubleshooting. They are not part of the standard HCI command set and are typically used in controlled environments. While initially described as a "backdoor," further clarifications labeled them as "undocumented debugging features." These commands are not accessible remotely via standard Bluetooth connections but could be interacted with if an entity has physical access to the device or operates in an HCI-UART configuration.
Espressif Systems provided clarification regarding these commands, stating that they are intended for debugging and do not pose a security risk under normal operating conditions. The company emphasized that these commands cannot be triggered remotely and are not used in standard Bluetooth operations. These commands are present only in ESP32 chips and are not included in the ESP32-C, ESP32-S, and ESP32-H series. To address concerns raised within the security community, Espressif announced that future versions of the ESP-IDF would include updates to restrict access to these debugging commands and improve documentation for vendor-specific HCI commands. These actions aim to provide additional transparency and ensure developers are well-informed about available functionalities.