Arduino Uno vs Mega 2560
Mega has 8× the flash, 4× the SRAM and 4× the pins of Uno — but costs 2–3× more. If your sketch fits in 32 KB and you use fewer than 14 digital pins, stay with Uno. Choose Mega only when you genuinely run out of pins or memory.
| Feature | Arduino Uno R3 | Arduino Mega 2560 |
|---|---|---|
| MCU | ATmega328P (8-bit, 16 MHz) | ATmega2560 (8-bit, 16 MHz) |
| Flash | 32 KB | 256 KB |
| SRAM | 2 KB | 8 KB |
| Digital I/O | 14 (6 PWM) | 54 (15 PWM) |
| Analog inputs | 6 | 16 |
| Serial ports | 1 | 4 |
| Best for | Everyday projects | Large I/O, RTOS, big libraries |
Pick Arduino Uno R3
You have < 14 devices to control and < 32 KB code.
- Cheaper
- Every shield fits
- Simpler wiring
Pick Arduino Mega 2560
You need many sensors/motors or heavy libraries.
- 54 digital pins
- 4 hardware UARTs
- 256 KB flash
FAQs
Does Mega run Uno shields?
Most Uno shields fit and work, but a few libraries rely on Uno's pin layout — always check compatibility.
Is Mega faster than Uno?
No — both run at 16 MHz. Mega just has more resources, not more speed.
