Arduino Nano Pinout
All Nano pin functions — including the analog-only A6/A7.
What it does: Look up the function and alternate functions of every Arduino Nano pin, and recognize the analog-read-only A6/A7.
When to use it: When wiring up a Nano, choosing function pins, or migrating from an Uno.
Disclaimer: This result is a reference estimate. For actual production, refer to the device datasheet / local regulations as authoritative.
~ = PWM? -capable; A6/A7 = Analog input only? .
| Pin | Category | Alternate functions | MCU | Notes |
|---|---|---|---|---|
| D0 | Digital | RX ← serial receive | PD0 | Used by upload/serial. |
| D1 | Digital | TX → serial transmit | PD1 | Used by upload/serial. |
| D2 | Digital | External interrupt INT0 | PD2 | |
| D3 | Digital | PWM ~ · External interrupt INT1 | PD3 | |
| D4 | Digital | General-purpose I/O | PD4 | |
| D5 | Digital | PWM ~ | PD5 | |
| D6 | Digital | PWM ~ | PD6 | |
| D7 | Digital | General-purpose I/O | PD7 | |
| D8 | Digital | General-purpose I/O | PB0 | |
| D9 | Digital | PWM ~ | PB1 | |
| D10 | Digital | PWM ~ · SPI SS | PB2 | |
| D11 | Digital | PWM ~ · SPI MOSI | PB3 | |
| D12 | Digital | SPI MISO | PB4 | |
| D13 | Digital | SPI SCK · On-board LED | PB5 | Connected to the on-board LED. |
| A0 | Analog | Analog input · Digital D14 | PC0 | |
| A1 | Analog | Analog input · Digital D15 | PC1 | |
| A2 | Analog | Analog input · Digital D16 | PC2 | |
| A3 | Analog | Analog input · Digital D17 | PC3 | |
| A4 | Analog | Analog input · I2C SDA | PC4 | Default I2C data line. |
| A5 | Analog | Analog input · I2C SCL | PC5 | Default I2C clock line. |
| A6 | Analog | Analog input (only) | ADC6 | ⚠ Analog input only — cannot be digital I/O, no internal pull-up. |
| A7 | Analog | Analog input (only) | ADC7 | ⚠ Analog input only — cannot be digital I/O, no internal pull-up. |
| VIN | Power/control | External supply input (7–12V) | — | Goes through the on-board regulator. |
| 5V | Power/control | 5V output / logic level | — | |
| 3V3 | Power/control | 3.3V output (≤50mA) | — | Supplied by the USB-serial chip (FT232/CH340); very low current. |
| GND | Power/control | Ground | — | Multiple GND pins at the same potential. |
| RST | Power/control | Reset (active-low) | PC6 | Pull low to reset the MCU. |
| AREF | Power/control | ADC reference voltage | — | Configure with analogReference(). |
MEANS D13 drives the on-board LED; A4/A5 double as I2C; A6/A7 can only read analog; PWM pins are marked ~. An alternate-function pin can only do one thing at a time.
No history yet. Each calculation is automatically saved to this device.
How to use the Arduino Nano pinout reference
Filter by category → check alternate functions → watch out for A6/A7.
- 01
Browse by category
Digital D0–D13, analog A0–A7, power/control; click the chips above to filter.
- 02
Spot the alternate functions
~ = PWM-capable; UART/SPI/I2C/external interrupts and ATmega328P ports are marked too.
- 03
Watch out for A6/A7
They can only read analog values and cannot act as digital I/O, nor do they have an internal pull-up.
Common function pins (same MCU as Uno)
The Nano uses the same ATmega328P as the Uno, so the function pins match.
| Function | Pin |
|---|---|
| PWM (~) | D3 · D5 · D6 · D9 · D10 · D11 |
| Hardware UART | D0=RX · D1=TX |
| SPI | D10=SS · D11=MOSI · D12=MISO · D13=SCK |
| I2C | A4=SDA · A5=SCL |
| Analog input only | A6 · A7 (no digital I/O) |
Official Arduino Nano pinout / ATmega328P.
Common questions, answered in 3 minutes
Are the Nano and Uno pins the same?
Same ATmega328P, so the digital/PWM/SPI/I2C/UART functions are identical. The differences: the Nano adds A6/A7 (analog only) and lacks the Uno IOREF pin.
Why can A6/A7 not be used as digital pins?
They are the chip's dedicated ADC6/ADC7 analog-input channels, not internally wired to a digital port and with no pull-up resistor — you can only analogRead them, not digitalRead/Write.
Can D13 be used as an input?
D13 is wired to the on-board LED, so high-impedance input readings are unreliable; using it as an output / to drive an LED is fine.
How much current can the 3V3 pin supply?
The Nano's 3V3 is provided by the USB serial chip (FT232/CH340) and the current is small (about ≤50mA), so don't drive large loads from it.
Does this table apply to the Nano Every / Nano 33?
No. This table is for the classic Nano (ATmega328P). The Nano Every (ATmega4809) and Nano 33 series use different chips — refer to their own pinouts as authoritative.
Standards and sources referenced by this tool
| Item | Value / Formula | Source |
|---|---|---|
| Pin functions | Nano / ATmega328P | Arduino official |
| A6/A7 | Analog input only (ADC6/7) | ATmega328P datasheet |
Refer to the official pinout / board silkscreen as authoritative; this table is for the classic Nano (ATmega328P).