Arduino VS NodeMCU

In this blog, we will be doing a comparison between Arduino and NodeMCU. We will discuss which is the best microcontroller in different applications. 

In the table below, we have given some common features of Arduino UNO and NodeMCU. 


Arduino UNO




Operating Voltage



Input Voltage

4.5V - 10V

7V - 12V

Current consumption

15uA -  400mA

45mA - 80mA

Current consumption Deep sleep



Digital I/O Pins



Digital I/O Pins with PWM



Analog Input Pins












DC Current per I/O Pin



Flash Memory







512 Bytes

1024 Bytes

Clock speed




58 mm

69 mm


31 mm

53 mm




Power jack



USB connection


USB type-B

Arduino VS NodeMCU

In this article we will be comparing the 2 microcontrollers. NodeMCU is a microcontroller development board with wifi capability. It uses an ESP8266 microcontroller chip. Whereas Arduino UNO uses an ATMega328P microcontroller. Besides the chip, it contains other elements such as crystal oscillator, voltage regulator, etc.

Now let's compare each feature of these 2 microcontrollers in brief. As per the data given in the above table.

Operating Voltage:

The operating voltage of NodeMCU is 3.3v and the operating voltage of Arduino UNO is 5V. 

Input Voltage:

The Input voltage is the same for both the microcontroller boards. The NodeMCU can be powered using voltages between 4.5V to 10V. The NodeMCU will also work with a maximum voltage of 12V. But always it is highly recommended to keep the input voltage between 4.5V to 10V. Next, we will see Arduino. The input voltage of the Arduino UNO is between 7V to 12V. The voltage between 7V to 12V has to be applied to the power jack of the Arduino UNO. The Arduino UNO will also work with the input voltage between 6V to 20V. But it is always recommended to keep the input voltage between 7V to 12V to be on a safer side.

Also Read - How to use Buzzer with Arduino

Current consumption:

The current consumption of the NodeMCU will be between 15uA to 400mA. The current consumption may be anywhere between 15uA to 400mA. And the Arduino UNO’s current consumption lies between 45mA to 85mA. The current will vary depending upon the task that the microcontroller board is performing based on the program it is running. In both the microcontroller the current consumption can be reduced to very less by using the microcontroller boards in deep sleep mode. The deep sleep mode current of the NodeMCU and Arduino UNO is 0.5uA and 35mA respectively.

Digital I/O pins (Digital input and output pins):

The NodMCU contains 14 digital pins and the Arduino UNO contains 16 digital pins. These are the pins used to connect the digital peripherals. In both the microcontroller boards, these pins perform the same task. But the operating voltages for both the microcontroller are different. The digital pins of the Arduino UNO work in both 3.3V and 5V. But the digital pins of NodeMCU work only on 3.3V, more than that the microcontroller gets damaged.

Digital I/O pins with PWM:

In NodeMCU all the digital pins i.e, 16 pins can be used as PWM pins programmatically. The Arduino UNO has only 6 pins for PWM.

Analog pins:

The NodeMCU contains only 1 pin analog pin. Whereas Arduino UNO contains 6 pins. These pins are used to measure analog signals.


The NodeMCU contains 2 SPI interfaces and the Arduino UNO contains 1 SPI interface. We can use a number of slaves to communicate with each other by connecting the peripherals in the daisy chain method.  


The NodeMCU and the Arduino UNO contain 1 I2C pin (SCL & SDA). But the NodeMCU and Arduino UNO works on different voltage levels. The voltage levels of SDA and SCL pins of the NodeMCU and Arduino UNO are 3.3V and 5V respectively.


The NodeMCU contains 2 UART interface pins and the Arduino UNO contains only 1 UART interface pin.

Current in each I/O pin:

Each pin of the NodeMCU can handle current up to 12mA only. More than this, the board might get damaged. And the Arduino UNO can handle up to 40mA of current per pin.

Flash memory:

The NodeMCU comes with a flash memory of 4MB capacity and the Arduino UNO comes with 32KB of flash memory. This is the memory in which the program which we upload is stored.


The NodeMCU comes with SRAM off 64KB and the Arduino UNO comes with the SRAM of 2KB.


The NodeMCU consists of 512 bytes EEPROM and the Arduino comes with 1024 bytes of EEPROM. 

Clock Speed:

The NodeMCU has a clock speed of 80MHz and the Arduino UNO has a clock speed of 16MHz.

Wifi connectivity: 

The NodeMCU has wifi connectivity which is most commonly used for IoT-based applications. The Arduino UNO does not come with the wifi connectivity feature.

Advantages of NodeMCU over Arduino UNO:

  • Better Processor & Memory: NodeMCu comes with an 80MHz of clock speed and 4MB of flash memory.
  • Built-in TCP/IP Stack - IoT Ready: The NodeMCU contains a Wifi connection and can connect to the internet through Wifi. It is best suited for IoT applications.
  • Cheaper: NodeMCU is an ESP8266 chip-based microcontroller development board, which is very cheap as compared to Arduino UNO.
  • Breadboard-friendly and compact: The NodeMCU can be easily inserted into a breadboard and test various circuit designs. Whereas Arduino UNO cannot be fit into the Breadboard.

Disadvantages of ModeMCU over Arduino UNO:

  • Need to learn how to program the new functionalities: For programming NodeMCU, we need knowledge about the web application, to program for a new project, we need to learn more about the web-based applications.
  • Analog pins: NodeMCu has only one Analog input pin. But the Arduino UNO contains 6 Analog pins.
  • Lower voltage level: The NodeMCU cannot be compatible with the other Modules in rare cases.

Advantages of Arduino UNO over NodeMCU:

  • Extensive support: The Arduino UNO has very good content online available and many people across the world participate in the Arduino community. Availability of learning content is more as compared to NodeMCU.
  • Easy Interface with sensors and actuators: Arduino UNO can be easily interfaced with different sensors and actuators, as it supports both 3.3V and 5V modules when compared to NodeMCU.
  • Voltage handling capability: The Arduino UNO can handle a voltage of 20V. But the NodeMCU can only withstand voltage up to 12V.
  • Current per pin: Arduino UNO can handle the current of 40mA per pin. But the NodeMCU can only handle the current of 12mA.

Disadvantages of Arduino UNO over NodeMCU:

  • Memory and Processor limitations: The Arduino UNO has lesser memory and processor capability as compared to NodeMCU. No built-in IoT capability. 
  • Costlier: The Arduino UNO is costlier than the NodeMCU
  • Non-breadboard friendly: The Arduino UNO cannot be inserted into the breadboard due to the size and pin orientation. 


Both the Microcontroller boards are good in the place where they are used. Depending upon the technical requirement, one can choose the best microcontroller board which matches their requirements. Both the boards have their own advantages and disadvantages over each other.

Frequently Asked Questions

1. Can NodeMCu be used as Arduino?

The answer is Yes. As same code can be used for both the microcontrollers when programming using Arduino IDE. But there will be some limitations like Voltage, Current, Analog input pins, etc.

2. Is NodeMCU is a microcontroller?

Yes, NodMCU is a microcontroller with additional features. As it supports Wifi connections and it is best suited for IoT-based applications.

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