Arduino Uno R4 vs SparkFun ESP32 Thing Plus
Side-by-side comparison of features, pricing, ratings, and alternatives.
The Arduino Uno R4 is the latest revision of the world's most popular beginner microcontroller board, now powered by a 32-bit Renesas RA4M1 processor - a major jump from the original 8-bit design while keeping the same beginner-friendly form factor and pin layout. It remains the standard starting point for electronics education, supported by an enormous library ecosystem and the simple Arduino IDE, making it approachable for students and hobbyists building their first circuits. The WiFi variant adds built-in wireless connectivity for IoT projects, while a built-in 12x8 LED matrix on the WiFi model enables simple visual output without extra components.
The SparkFun ESP32 Thing Plus is a small, breadboard‑friendly development board that packs a dual‑core ESP32‑WROOM‑32U module, USB‑C power and programming, and a rich set of peripherals. It’s designed for rapid prototyping of IoT, wearables, and sensor projects while keeping the footprint low. With built‑in voltage regulators, a reset button, and a Qwiic‑compatible I2C header, the board offers both flexibility and ease of use for hobbyists and engineers alike. Its open‑hardware design encourages community contributions and custom extensions.
Around $20-27 depending on the variant.
- Extremely beginner-friendly
- Huge tutorial and library ecosystem
- Backward compatible with existing shields
- Affordable entry point
- USB‑C simplifies power and programming
- Rich peripheral set including Qwiic and breadboard pins
- Robust Wi‑Fi and Bluetooth performance
- Fully open‑hardware with extensive community support
- Less powerful than Raspberry Pi for compute-heavy tasks
- No built-in display or OS
- WiFi variant costs more
- No built‑in battery management circuitry
- Limited GPIO count compared to larger dev kits
- No Ethernet port for wired networking
What reviewers say
Arduino Uno R4 Reviews
4.5 (2)Highly recommend Arduino Uno R4
I picked up Arduino Uno R4 a while back and haven't looked back. Huge tutorial and library ecosystem. One minor gripe: wifi variant costs more, but it hasn't been a dealbreaker. Would recommend.
Does exactly what we need
Been a regular user of Arduino Uno R4 for a while now. Affordable entry point. No major complaints so far. Would recommend.
SparkFun ESP32 Thing Plus Reviews
No reviews yet.
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Compact ESP32 board with touch screen, battery and sensors for rapid IoT prototyping
A tiny Wi-Fi development kit for creating connected IoT devices and prototypes.
A compact and versatile development board powered by the ESP32 microcontroller for IoT applications.
The Verdict
AI-generated from listing dataThe Arduino Uno R4 is the safer default for beginners needing easy setup and shield compatibility, while the SparkFun ESP32 Thing Plus offers higher performance and modern connectivity for IoT projects.
Key differences
- •Processor: 32‑bit Renesas 48 MHz (Uno R4) vs dual‑core Tensilica 240 MHz (ESP32)
- •Connectivity: Optional Wi‑Fi on Uno R4 vs built‑in Wi‑Fi + Bluetooth 5.0 on ESP32
- •Form factor: Uno R4 supports classic Arduino shields; ESP32 uses breadboard layout with Qwiic sockets
- •Open‑source: Both are open, but ESP32 provides full schematics and GitHub code; Uno R4 only mentions open source
- •Warranty: ESP32 specifies 2‑year warranty; Uno R4 lists only forum/documentation support
Performance
ESP32 runs up to 240 MHz dual‑core, far faster than Uno R4’s 48 MHz Renesas processor.
Build quality
Both are hobby‑grade boards; no specific build quality details provided.
Connectivity
ESP32 includes built‑in Wi‑Fi and Bluetooth 5.0; Uno R4 Wi‑Fi is optional and adds cost.
Power & efficiency
Uno R4’s lower‑speed processor generally consumes less power; ESP32’s higher performance draws more.
Compatibility
Uno R4 is backward compatible with classic Uno shields, a huge ecosystem for beginners.
Price & value
Uno R4 priced around $20‑27; ESP32 listed at $19.95 but lacks battery management, affecting total system cost.
Warranty & support
ESP32 specifies a 2‑year warranty; Uno R4 only offers forums and documentation.
Choose Arduino Uno R4 if…
Beginners or educators needing shield compatibility and simple setup.
Choose SparkFun ESP32 Thing Plus if…
IoT developers needing higher compute, Wi‑Fi/Bluetooth, and open‑hardware schematics.
Common questions
Which board is cheaper overall?
Both list similar base prices (~$20); however, the Uno R4’s Wi‑Fi variant costs more, while ESP32 includes Wi‑Fi by default.
Can I use existing Arduino Uno shields with the ESP32 board?
No; the ESP32 uses a breadboard layout and Qwiic sockets, not the Uno shield footprint.
Do either boards include battery management for portable projects?
Only the ESP32 mentions no built‑in battery management; the Uno R4 does not specify battery features either.