ESP32-C3-DevKitM-1
The ESP32-C3-DevKitM-1 is the most cost-effective board in the ESP32 lineup, combining a single-core RISC-V processor at 160MHz with WiFi and BLE 5.0 in a compact package. At roughly seven dollars, it delivers modern wireless connectivity with the lowest deep sleep current of any ESP32 variant at 5uA.
Best budget ESP32 for simple WiFi/BLE sensors, skip if you need dual-core performance or camera support.
Where to Buy
Pros
- 5uA deep sleep current — lowest in the ESP32 family for maximum battery life
- BLE 5.0 with Long Range (Coded PHY) support for extended wireless reach
- RISC-V architecture is open-standard and increasingly well-supported
- USB 2.0 CDC for programming without a separate UART bridge chip
Cons
- Single-core RISC-V at 160MHz — noticeably slower than dual-core Xtensa LX7 boards
- No PSRAM — limits buffer sizes for complex data processing
- Only 22 GPIO pins — restricting for projects with many peripherals
- 6 ADC channels versus 18-20 on larger ESP32 boards
RISC-V Architecture
The ESP32-C3 is Espressif's first RISC-V chip, using a single 32-bit core clocked at 160MHz. The RISC-V ISA is open-standard, which means growing toolchain support from GCC, LLVM, and Rust. For developers invested in the RISC-V ecosystem, the C3 is a practical entry point.
The single-core limitation is real but manageable. The WiFi and BLE stacks are well-optimized for single-core operation, and for typical IoT workloads — read sensor, format data, transmit, sleep — the 160MHz RISC-V core is more than sufficient. You will feel the constraint if you try to run a web server while simultaneously processing sensor data.
Power Efficiency
The C3's 5uA deep sleep current is the standout spec. For context, a CR2032 coin cell battery has approximately 225mAh of capacity. At 5uA continuous draw in deep sleep, the C3 could theoretically last over 5 years on a single coin cell — though real-world duty cycles with periodic WiFi transmissions will reduce this significantly.
Compared to the ESP32-S3 at 7uA and the original ESP32 at 10uA, the C3's power efficiency gives it a clear edge in battery-powered deployments. If your project runs on a battery and wakes periodically to transmit data, the C3 should be your default choice.
Connectivity
WiFi 802.11 b/g/n and BLE 5.0 is a modern wireless combination. The BLE 5.0 upgrade from the original ESP32's BLE 4.2 is meaningful: 2x data throughput (2 Mbps vs 1 Mbps), 4x range with Coded PHY, and support for BLE mesh networking.
The absence of Thread and WiFi 6 is notable. For new smart home installations targeting the Matter protocol over Thread, the ESP32-C6 is the better choice. But for standard WiFi + BLE sensor networks, the C3 covers all the bases at a lower price point and power draw.
Full Specifications
Processor
| Specification | Value |
|---|---|
| Architecture | RISC-V |
| CPU Cores | 1 |
| Clock Speed | 160 MHz |
Memory
| Specification | Value |
|---|---|
| Flash | 4 MB |
| SRAM | 400 KB |
Connectivity
| Specification | Value |
|---|---|
| WiFi | 802.11 b/g/n |
| Bluetooth | 5.0 |
I/O & Interfaces
| Specification | Value |
|---|---|
| GPIO Pins | 22 |
| ADC Channels | 6 |
| SPI | 3 |
| I2C | 1 |
| UART | 2 |
| USB | USB 2.0 (CDC) |
Power
| Specification | Value |
|---|---|
| Input Voltage | 5 V |
| Deep Sleep Current | 5 uA |
Physical
| Specification | Value |
|---|---|
| Dimensions | 53.6 x 25.4 mm |
| Form Factor | Standard breadboard |
Who Should Buy This
5uA deep sleep is the lowest in the ESP32 family. Wake every 15 minutes, read a sensor, transmit via WiFi or BLE, go back to sleep. A 2000mAh battery lasts years at this duty cycle.
BLE 5.0 with Coded PHY extends range to 400m+ line-of-sight. Low power draw makes it viable for coin-cell-powered beacons.
Single core at 160MHz and no PSRAM make video processing impossible. The ESP32-S3 with 8MB PSRAM and camera interface is designed for this.
Better alternative: ESP32-S3-DevKitC-1
Only 6 ADC channels and 22 GPIO pins. The original ESP32-DevKitC has 18 ADC channels and 34 GPIO pins.
Better alternative: ESP32-DevKitC V4
Supports Matter over WiFi, but lacks Thread for mesh networking. The ESP32-C6 adds WiFi 6 and Thread for full Matter support.
Better alternative: ESP32-C6-DevKitC-1
Frequently Asked Questions
Is the ESP32-C3 fast enough for a web server?
Yes, for simple REST APIs and small web pages. The single core at 160MHz handles HTTP requests adequately. For complex web applications with concurrent connections, the dual-core ESP32-S3 at 240MHz is a better fit.
Can the ESP32-C3 run Arduino code?
Yes. Arduino IDE and PlatformIO both support the ESP32-C3 with the ESP32 Arduino Core. Most Arduino libraries written for ESP32 work without modification, though some that use Xtensa-specific assembly will need RISC-V alternatives.
ESP32-C3 vs ESP32-C6: what is the difference?
The C6 adds WiFi 6 (802.11ax), BLE 5.3, Thread, Zigbee, and a low-power RISC-V co-processor. The C3 has WiFi 4 and BLE 5.0 only. Choose the C6 for smart home/Matter projects; choose the C3 for budget sensors.
Does the ESP32-C3 support Rust?
Yes. Espressif actively maintains Rust support for RISC-V ESP32 chips including the C3. The esp-rs project provides HAL crates, and the RISC-V target is well-supported by the Rust compiler.
How long does an ESP32-C3 last on a battery?
At 5uA deep sleep current, a 2000mAh LiPo battery lasts over 45 years in sleep alone. Real-world battery life depends on wake frequency and WiFi transmission duration. Waking every 15 minutes to send a BLE packet, expect 1-2 years on a CR2032.