ESP32-S3 vs ESP32-C3: Which New ESP Chip to Choose

Choosing between the ESP32-S3 and ESP32-C3 is a decision every IoT developer faces when starting a new project. Both chips from Espressif Systems represent the latest generation of the ESP32 family, but they target very different use cases. The ESP32-S3 is a powerhouse with AI acceleration and USB-OTG, while the ESP32-C3 is a lean, cost-effective RISC-V chip for simple IoT applications. This guide breaks down every important difference to help you make the right choice.

Table of Contents

• Overview: The New ESP32 Generation
• Hardware Specifications Compared
• AI and Machine Learning Capabilities
• Wireless Performance: WiFi and Bluetooth
• USB Support and Connectivity
• Power Consumption and Battery Life
• Development Boards Available in India
• Frequently Asked Questions
• Conclusion

Overview: The New ESP32 Generation

The original ESP32 (2016) revolutionised IoT development with its dual-core processor, WiFi, and Bluetooth at an incredibly low price. Espressif has since released several variants, each optimised for different use cases:

• ESP32-S3 (2021): Dual-core Xtensa LX7 at 240 MHz with vector instructions for AI/ML, USB-OTG, and support for larger PSRAM and flash. It is the premium chip in the family.
• ESP32-C3 (2020): Single-core RISC-V at 160 MHz. The budget-friendly option designed to replace ESP8266 with modern WiFi and BLE 5.0 support.

Both chips support WiFi 4 (802.11 b/g/n) and Bluetooth LE 5.0, run ESP-IDF and Arduino frameworks, and are 3.3V logic. The differences lie in processing power, peripherals, and specialised features.

Hardware Specifications Compared

AI and Machine Learning Capabilities

The ESP32-S3’s biggest advantage is its vector extension instructions. These SIMD (Single Instruction, Multiple Data) operations accelerate neural network inference by processing multiple data points in parallel. Espressif reports up to 3-4x speedup for quantised INT8 models compared to the original ESP32.

Practical AI applications on ESP32-S3:

• Keyword spotting: Wake word detection (“Hey device”) running locally without cloud
• Image classification: Simple object recognition with camera input (person detection, gesture recognition)
• Anomaly detection: Vibration pattern analysis for predictive maintenance
• Audio classification: Environmental sound recognition (glass break, baby cry)

The ESP32-C3, with its single RISC-V core and no vector instructions, is not suitable for on-device AI. If your project needs any machine learning inference, the ESP32-S3 is the only choice between the two.

// ESP32-S3 TensorFlow Lite Micro - Person Detection Example
#include "tensorflow/lite/micro/micro_interpreter.h"
#include "person_detect_model.h"
#include "esp_camera.h"

// ESP32-S3 vector instructions are used automatically
// by TFLite Micro's optimised kernels
const int kTensorArenaSize = 136 * 1024;
uint8_t tensor_arena[kTensorArenaSize];

void setup() {
    // Initialise camera (DVP interface - S3 only)
    camera_config_t config;
    config.pixel_format = PIXFORMAT_GRAYSCALE;
    config.frame_size = FRAMESIZE_96X96;
    esp_camera_init(&config);

    // Load TFLite model
    // Model runs ~10x faster on S3 vs C3 for INT8 inference
}

Wireless Performance: WiFi and Bluetooth

Both chips support WiFi 4 (2.4 GHz, 802.11 b/g/n) and Bluetooth LE 5.0. However, there are differences:

• WiFi throughput: ESP32-S3 achieves slightly higher throughput (~20 Mbps vs ~15 Mbps) due to its faster processor handling network stack operations.
• Bluetooth Classic: Neither chip supports Bluetooth Classic (SPP, A2DP). If you need classic Bluetooth, use the original ESP32.
• BLE 5.0 features: Both support coded PHY for extended range (up to 2x distance at reduced data rate) and 2M PHY for higher throughput.
• Antenna: Both support PCB antenna and external antenna via U.FL connector, depending on the module variant.

For most IoT applications, the wireless performance difference is negligible. Choose based on other factors.

USB Support and Connectivity

This is where the ESP32-S3 truly shines. Its USB-OTG (On-The-Go) controller supports both USB Host and USB Device modes:

USB Device Mode (both chips)

The ESP32-S3 can appear as a USB HID (keyboard/mouse), USB CDC (serial), USB MSC (mass storage), USB audio, or custom USB device. The ESP32-C3 only has a built-in USB Serial/JTAG controller for programming and debugging — it cannot emulate other USB device types.

USB Host Mode (ESP32-S3 only)

The ESP32-S3 can act as a USB host, connecting to USB devices like keyboards, mice, flash drives, MIDI controllers, and game controllers. This opens up entirely new application possibilities.

// ESP32-S3 as USB Keyboard (Device Mode)
#include "USB.h"
#include "USBHIDKeyboard.h"

USBHIDKeyboard Keyboard;

void setup() {
    Keyboard.begin();
    USB.begin();
}

void loop() {
    if (digitalRead(0) == LOW) {  // Button press
        Keyboard.print("Hello from ESP32-S3!");
        delay(500);
    }
}

Power Consumption and Battery Life

For battery-powered IoT devices, power consumption is critical:

The ESP32-C3 is more power-efficient across all modes thanks to its single core and RISC-V architecture. For a battery-powered sensor that wakes every 15 minutes to send data, the C3 will last 20-30% longer on the same battery.

Development Boards Available in India

ESP32-S3 Boards

The ESP32-S3 is available in numerous development board configurations, many featuring built-in displays:

• ESP32-S3 DevKitC-1: Basic development board with USB-C, 44 GPIO pins exposed
• Waveshare ESP32-S3 with Display: Range of boards with 1.47 to 7-inch displays, ideal for HMI projects
• ESP32-S3-CAM: Camera module boards for vision projects
• Waveshare ESP32-S3-Nano: Arduino Nano form factor for compact designs

ESP32-C3 Boards

• ESP32-C3 DevKitM-1: Basic development board from Espressif
• Seeed XIAO ESP32-C3: Ultra-compact (21x17mm) board, popular for wearables
• ESP32-C3 SuperMini: Budget-friendly tiny board with USB-C

Frequently Asked Questions

Can ESP32-C3 run a camera?

No. The ESP32-C3 lacks a DVP camera interface. For camera projects, use the ESP32-S3 or the original ESP32 (ESP32-CAM). The S3 has a dedicated camera interface supporting up to 2MP resolution.

Which chip should I use for a simple temperature sensor with WiFi?

ESP32-C3. It is cheaper, lower power, and has more than enough processing power for reading sensors and sending data over WiFi or MQTT. Using an ESP32-S3 for this would be overkill.

Can I use Arduino IDE with both chips?

Yes. Both are fully supported in the Arduino-ESP32 board package. Install it from the Arduino Board Manager and select either “ESP32S3 Dev Module” or “ESP32C3 Dev Module” as your target.

Is RISC-V (ESP32-C3) better than Xtensa (ESP32-S3)?

RISC-V is an open-source ISA with growing industry support, while Xtensa is Cadence’s proprietary architecture. For end users, the architecture matters less than the chip’s features and performance. Choose based on your project needs, not the ISA.

Which chip has better community support?

The original ESP32 still has the largest community. Between S3 and C3, the ESP32-S3 has more community projects and examples due to its richer feature set. However, both are well-supported by Espressif’s documentation and forums.

Conclusion

The choice between ESP32-S3 and ESP32-C3 comes down to your project’s needs. Choose the ESP32-S3 for camera projects, AI/ML inference, USB device/host applications, display-heavy interfaces, or when you need maximum processing power. Choose the ESP32-C3 for simple IoT sensors, battery-powered devices, cost-sensitive production runs, or when you just need WiFi and BLE in the smallest possible package.

Both chips represent a significant upgrade over the original ESP32 in terms of security (secure boot, flash encryption) and BLE 5.0 support. Whichever you choose, you are building on a mature, well-documented platform with excellent tooling and community support.

Explore our full range of ESP32 development boards at Zbotic to find the perfect board for your IoT project.