Exploring the ESP32 versions. Differences and similarities.

ESP32 is a series of SoCs, that has become known for its integrated WiFi and Bluetooth while keeping its low cost. The ESP32 is designed and manufactured by Espressif Systems, the Chinese semiconductor company that specializes in the design and production of Wi-Fi and Bluetooth-enabled microcontrollers and systems-on-a-chip or SoCs.

Since the original ESP32 release, plenty of different versions of ESP32 were released. Starting with the already available SoCs, such as ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C5 and ESP32-C6 and finishing with the latest announcements, such as ESP32-H2 and ESP32-P4.

In this post, we will explore the currently available ESP32 microcontrollers on the market. We will go through the different versions of ESP32 by the release date, do the esp32 version comparison and will see their differences, similarities and the upgrade path, from the original ESP32 to the newest ESP32-C5:

• ESP32 Series
• ESP32-S2
• ESP32-S3
• ESP32-C3
• ESP32-C6
• ESP32-H2
• ESP32-C2
• ESP32-C5
• ESP32-P4

ESP32 Series #

Normally, the ESP32-WROOM Module costs around 4$.

The prices are subject to change. Check current price:

ESP32 is the original ESP microcontroller, that was announced in 2016. It features the Xtensa dual-core 32bit LX6 processor, that provides a clock frequency of up to 240 MHz.

When it comes to memory, it has 520 KB of SRAM, 448 KB ROM and up to 4 MB Flash memory.

The ESP32 chip supports 2.4 GHz WiFi (IEEE 802.11 b/g/n), which has speeds up to 150 Mbps and Bluetooth Low Energy (BLE) 4.2.

The original ESP32 in deep-sleep mode consumes around 100uA power.

The ESP32 Series includes various module models like the popular ESP32-WROOM, ESP32-WROVER, and ESP32-MINI series, each tailored for different applications.

• The WROOM modules are versatile, featuring WiFi and Bluetooth connectivity, and are commonly used in IoT devices due to their compact size and affordability.

• The WROVER modules include additional PSRAM, making them ideal for applications requiring more memory, such as video streaming or advanced GUIs.

• Smaller modules like the ESP32-MINI are designed for size-constrained projects, providing the same core functionality in a more compact form factor. These modules are pre-certified, simplifying the development and deployment process for IoT projects.

Check ESP32 Series boards with USB-C.

ESP32S2 Series #

Normally, the ESP32-S2 Module costs around 6$.

The prices are subject to change. Check current price:

ESP32-S2 is the first ESP32 successor version, that was announced in 2019. It is the successor to the ESP32 chip, focusing its design for low-power and high-performance applications. The ESP32S2 features a single-core 32bit Xtensa LX7 processor, that provides the same clock frequency, as the previous Xtensa LX6, of up to 240 MHz.

As the ESP32-S2 is more focused on low power, it has less SRAM, which comes at 320 KB, 128 KB ROM and up to 4 MB flash memory.

The ESP32S2 chip supports 2.4 GHz WiFi (802.11 b/g/n)**, which provides a speed of up to 150 MBps, but unlike the original ESP32 does not have integrated Bluetooth.

Compared to the original ESP32, the ESP32S2 consumes 5 times less power in deep-sleep mode, specifically rated at 22uA.

Check ESP32-S2 Series boards with USB-C.

ESP32S3 Series #

Normally, the ESP32 S3 Module costs around 4$.

The prices are subject to change. Check current price:

At the end of 2020, Espressif Systems also announced the ESP32-S3 chip. It comes with the same Xtensa dual-core 32bit LX7 processor, as the ESP32S2, and has the same clock speed of up to 240 MHz.

The ESP32-S3 provides a similar amount of processing memory to the original ESP32, specifically 512 KB of SRAM, 384 KB ROM and double the size of flash memory of up to 8 MB.

The ESP32S3 chip supports 2.4 GHz WiFi (802.11 b/g/n), with a speed of up to 150 MBps and Bluetooth Low Energy (BLE) 5.0.

The main difference, compared to the previous versions of ESP32 is the AI Acceleration Support, which provides the acceleration for neural network computing and signal processing.

Check ESP32-S3 Series boards with USB-C.

ESP32C3 Series #

Normally, the ESP32 C3 Module costs around 4$.

The prices are subject to change. Check current price:

The same year, as the ESP32S3 were announced, Espressif Systems also announced the ESP32C3. It is the first ESP32 chip, that comes with the RISC-V. ESP32-C3 features a single-core 32bit RISC-V processor, that has a clock speed of 160 MHz.

The ESP32C3 provides 400 KB of SRAM, 384 KB ROM and up to 4 MB flash memory.

This chip supports the 2.4 GHz WiFi (802.11 b/g/n), with the same up to 150 MBps speed as the previous versions and the Bluetooth Low Energy (BLE) 5.0.

The ESP32C3's main focus is security and provides the features, such as Secure Boot, Flash Encryption, Digital Signature and HMAC Peripheral.

Check ESP32-C3 Series boards with USB-C.

ESP32C6 Series #

Normally, the ESP32 C6 Module costs around 4$.

The prices are subject to change. Check current price:

The next version of the ESP32 microcontrollers, the ESP32-C6, was announced in 2021. It comes with the same single-core 32-bit RISC-V processor, as the ESP32C3 and has a clock frequency of 160 MHz.

When it comes to memory, it has 512 KB of SRAM, 320 KB ROM and up to 4 MB Flash memory.

The ESP32C6 is the first ESP chip, that comes with the 2.4 GHz WiFi 6 (802.11ax) and also supports the 802.11 b/g/n for backward compatibility. Additionally, it comes with the Bluetooth Low Energy (BLE) 5.3 radio.

This chip's main focus is connectivity. It comes with WiFi 6 support and supports the OFDMA (Orthogonal Frequency Division Multiple Access) and MU-MIMO capabilities to work with low latency networks in highly congested wireless environments.

Also, the ESP32C6 provides 802.15.4 radio connectivity, used by Thread and Zigbee protocols. It enables the Matter-compliant WiFi endpoint devices and Thread endpoint devices.

Check ESP32-C6 Series boards with USB-C.

ESP32H2 Series #

Normally, the ESP32 H2 Module costs around 3$.

The prices are subject to change. Check current price:

The ESP32-H2 was announced in 2021. It features a single-core 32-bit RISC-V processor, operating at a clock frequency of 96 MHz, optimized for efficiency in resource-constrained environments.

In terms of memory, the ESP32-H2 includes 256 KB of SRAM and 128 KB of ROM, with support for external Flash memory for additional storage needs.

What sets the ESP32-H2 apart is its focus on mesh networking and low-power connectivity. It integrates 802.15.4 radio connectivity, which is foundational for Thread and Zigbee protocols, enabling scalable mesh networks. This makes the ESP32-H2 ideal for Matter-compliant devices in smart home ecosystems.

The chip also supports Bluetooth Low Energy (BLE) 5.0, offering enhanced data throughput and extended range for seamless communication with other BLE devices.

Designed for efficient communication in dense network environments, the ESP32-H2 provides reliability and power-saving features, making it a strong choice for devices requiring Thread and Zigbee interoperability.

ESP32C2 Series #

Normally, the ESP32 C2 Module costs around 4$.

The prices are subject to change. Check current price:

One of the latest ESP32 versions, the ESP32-C2 was announced in 2022. It comes with a 32-bit single-core RISC-V processor, with a frequency of 120 MHz.

The ESP32C2 provides 272 KB of SRAM, 576 KB ROM and up to 4 MB flash memory.

This chip supports a 2.4 GHz WiFi (802.11 b/g/n), with a speed of up to 150 MBps and a Bluetooth Low Energy (BLE) 5.0.

This ESP version comes in a small package with a size of 4mm x 4mm while keeping robust connectivity options and security standards.

ESP32C5 Series #

The ESP32-C5 was announced in the same year as ESP32-C2 2022. It comes with the 32-bit single-core RISC-V, which provides a clock frequency of 240 MHz.

It comes with the same sizes of memory, as the ESP32C3 - 400 KB SRAM, 384 KB ROM and up to 4 MB flash memory.

The main focus of this chip is again the connectivity improvements. It is the first ESP32 chip, that supports the 5 GHz WiFi 6 (802.11ax), together with the 802.11 b/g/n for backwards compatibility. If you want to read more about the ESP32-C5 WiFi, you can check our Connecting ESP32 to 5 GHz WiFi post. Also, ESP32-C5 provides Bluetooth Low Energy (BLE) 5.2 connectivity.

As mentioned, ESP32-C5 provides the WiFi 6 with 5 GHz frequency, which allows the development of IoT projects with more stability, lower latency and lower congestion wireless connection.

It is worth noting, that the ESP32-C5 currently is exclusive and very hard to find on the market.

ESP32P4 Series #

The ESP32-P4 was anounced in 2023. It features a dual-core 32-bit RISC-V processor running at up to 400 MHz, with an additional low-power core operating at 40 MHz for energy-efficient tasks.

The chip includes 768 KB of on-chip SRAM and 8 KB of zero-wait TCM RAM, ensuring smooth operation even in demanding scenarios. For applications requiring more memory, the ESP32-P4 supports external PSRAM. While it lacks built-in wireless connectivity, the device can seamlessly integrate with external wireless modules using interfaces like SPI, SDIO, or UART.

The ESP32-P4 excels in HMI applications, featuring advanced display and camera support through MIPI-CSI and MIPI-DSI interfaces. It supports capacitive touch inputs and speech recognition, making it ideal for interactive systems. The integrated Pixel Processing Accelerator (PPA) further enhances its capabilities in GUI rendering and media encoding, including H.264 video support.

Security is a core strength of the ESP32-P4, with features such as Secure Boot, Flash Encryption, and hardware-based cryptographic accelerators. It also includes a dedicated Key Management Unit and mechanisms for access protection, ensuring robust security for sensitive applications.

ESP32 versions comparison #

To get a better view of the similarities and differences between the ESP32 microcontrollers, discussed above, let's take a look at the esp32 comparison table, or more specifically the esp32 variants comparison:

From the ESP32 comparison, we can see that the original ESP32 series and ESP32-S series come with the Xtensa processor and operate at a frequency of up to 240 MHz, while the ESP32-C series and newer ESP32-H2 and ESP32-P4 chips come with the RISC-V processor. The clock frequencies in the RISC-V series range from 96 MHz (ESP32-H2) to 400 MHz (ESP32-P4).

Processing Memory #

All the chips provide similar processing memory sizes, but the ESP32-S2 comes with the lowest SRAM size of 320 KB. For ROM, the ESP32-S2 also has the smallest size at 128 KB. If you need more processing memory, the ESP32-C6 offers 512 KB SRAM and 320 KB ROM, making it a great option for memory-intensive tasks. The embedded flash memory is consistent across most models at up to 4 MB, except for the ESP32-S3, which offers up to 8 MB flash memory.

Connectivity #

Every ESP32 chip comes with inbuilt WiFi support, starting from 802.11 b/g/n in the original ESP32 to more advanced connectivity options in the newer models. The ESP32-C6 supports WiFi 6 (802.11 ax) at 2.4 GHz, while the ESP32-C5 provides WiFi 6 with 5 GHz support, making them standout options for advanced wireless communication. The ESP32-H2 and ESP32-P4 are exceptions as they do not include WiFi connectivity.

For Bluetooth, most ESP32 versions have built-in BLE, except for the ESP32-S2 and ESP32-P4, which lack Bluetooth functionality. The ESP32 originally supported BLE 4.2, while newer models like the ESP32-S3, ESP32-C2, and ESP32-C3 come with BLE 5.0. The latest versions, ESP32-C5 and ESP32-C6, support BLE 5.2 and BLE 5.3, respectively, offering significant improvements in range, speed, and energy efficiency.

GPIO and Deep Sleep Power #

Different versions of the ESP32 series have varying numbers of GPIO pins. The ESP32-C2 offers the lowest count at 14 GPIO pins, while the ESP32-S3 provides the highest with 45 GPIO pins. For applications requiring more pins, the ESP32-S series is a better choice due to their larger packages and higher GPIO count.

Power consumption in deep sleep mode is another critical factor. The original ESP32 consumes around 100 µA in deep sleep, but newer versions like the ESP32-S2 reduce this to 22 µA, and the ESP32-C series further drops it to 5 µA, making them ideal for ultra-low-power applications.

Package Sizes #

The package sizes of the ESP32 chips also vary. The ESP32-C2 is the smallest, with a 4 mm x 4 mm package, while other ESP32-C series chips, including the ESP32-H2, come in 5 mm x 5 mm sizes. The ESP32-S series is slightly larger, measuring 7 mm x 7 mm, which accommodates additional GPIO pins and features.

Unique Features #

The ESP32-C6 stands out for its advanced connectivity. Along with WiFi 6 and BLE 5.3, it includes 802.15.4 radio connectivity for Thread and Zigbee protocols, making it a strong choice for mesh networking in IoT ecosystems. Additionally, the ESP32-H2 provides 802.15.4 radio as its primary connectivity feature, focusing on Zigbee and Thread support. On the other hand, the ESP32-P4 is designed for high-performance tasks with dual-core RISC-V processors, extensive GPIO options, and interfaces for HMI and AI applications.

Versus Battles #

With all the different ESP32 options available, it's common to wonder, "What's the difference between ESP32-C3 and ESP32-S3?" or "How does ESP32-C6 compare to ESP32-H2?" Let's explore some of these Versus Battles to highlight the key differences and help you decide which chip suits your needs best.

ESP32 vs ESP32-S2 #

One of the key differences between the ESP32 and the ESP32-S2 is that the ESP32 comes with a dual-core LX6 processor, while the ESP32-S2 has a single-core LX7 CPU, making it less powerful. The ESP32 also has more ROM and SRAM than the ESP32-S2, but both have the same Flash memory capacity. A notable limitation of the ESP32-S2 is the lack of Bluetooth connectivity, while the ESP32 supports BLE 4.2. However, the ESP32-S2 offers lower power consumption, making it better for battery-powered projects.

ESP32-S3 vs ESP32-C3 #

The ESP32-S3 and ESP32-C3 differ mainly in their processor architecture. The ESP32-S3 features a dual-core LX7 processor, while the ESP32-C3 has a single-core RISC-V CPU, which offers better efficiency. The ESP32-C3 has a smaller form factor (4x4 mm) compared to the S3 (7x7 mm), making it better for compact devices. Additionally, the ESP32-S3 supports Bluetooth 5.0, while the ESP32-C3 provides the same version of Bluetooth but with a more power-efficient single-core architecture.

ESP32C3 vs ESP32C6 #

Both chips belong to the RISC-V family, but the ESP32-C6 is the newer and more advanced version. It comes with BLE 5.3, while the ESP32-C3 supports BLE 5.0. Additionally, the ESP32-C6 introduces WiFi 6 (802.11 ax) and 802.15.4 connectivity for Thread and Zigbee, making it a superior choice for smart home and IoT applications. The ESP32-C3, on the other hand, is ideal for simpler projects due to its smaller size and lower complexity.

ESP32-H2 vs ESP32-C6 #

Both the ESP32-H2 and the ESP32-C6 provide 802.15.4 radio connectivity, enabling support for Thread and Zigbee protocols. However, the ESP32-H2 focuses exclusively on low-power mesh networking without WiFi, while the ESP32-C6 combines WiFi 6, BLE 5.3, and 802.15.4 in a single chip. If your project requires WiFi alongside Zigbee/Thread, the ESP32-C6 is the better choice. For low-power, battery-operated devices using only Zigbee or Thread, the ESP32-H2 excels.

ESP32-S2 vs ESP32-S3 #

The ESP32-S2 is a less powerful version of the ESP32-S3. It has a single-core LX7 CPU, while the S3 offers a dual-core processor. Both chips support Bluetooth 5.0, but the ESP32-S3 consumes less power while delivering much more processing power. Additionally, the S3 supports up to 8 MB Flash memory, compared to the S2's 4 MB maximum.

ESP32 vs ESP32-C6 #

The ESP32-C6 introduces RISC-V architecture, replacing the Xtensa LX6 processor in the original ESP32. The C6 comes with BLE 5.3 and 802.15.4 for Zigbee and Thread protocols, which the original ESP32 lacks. Additionally, the ESP32-C6 supports WiFi 6 (802.11 ax), compared to the older WiFi 4 (802.11 b/g/n) on the ESP32.

ESP32-P4 vs ESP32-S3 #

The ESP32-P4 stands out for its dual-core RISC-V processor with a frequency of up to 400 MHz, far exceeding the dual-core LX7 processor of the ESP32-S3. However, the ESP32-P4 does not include WiFi or Bluetooth, focusing instead on HMI applications with features like MIPI-DSI for displays, MIPI-CSI for cameras, and AI accelerators. The ESP32-S3, with its wireless connectivity, is better suited for IoT applications requiring communication capabilities.

ESP32-H2 vs ESP32-C3 #

The ESP32-H2 focuses on 802.15.4 mesh networking for Thread and Zigbee, while the ESP32-C3 is a more general-purpose chip with WiFi (802.11 b/g/n) and Bluetooth 5.0 BLE. The ESP32-H2 is ideal for battery-powered devices that rely on Zigbee or Thread, while the ESP32-C3 suits projects needing both WiFi and BLE in a small form factor.

Conclusion #

We have explored the different versions of ESP32 SoCs and their features, differences and similarities. Hopefully, you should now have a better background on the ESP32 options and their provided specifications, connectivity options, peripherals and more. To conclude, in our opinion, there is no best ESP32 microcontroller, as it all comes to the needs, features and requirements of your project.