USB-A Pinout
The classic flat 4-pin USB 2.0 Standard-A plug - power and one data pair.
Overview
USB-A (Standard-A) is the familiar flat rectangular USB plug found on hosts like PCs and chargers. The USB 2.0 version has four contacts: 5 V power, the D+/D- data pair, and ground.
Power pins (1, 4) are longer than the data pins so power mates first on insertion. USB 1.x and 2.0 share this identical 4-pin layout.
Pinout
| Pin | Name | Function | Description |
|---|---|---|---|
| 1 | VBUS | POWER | +5 V bus power |
| 2 | D- | USB2 / PAIR / DATA | USB 2.0 data, negative of the differential pair |
| 3 | D+ | USB2 / PAIR / DATA | USB 2.0 data, positive of the differential pair |
| 4 | GND | GND / SIGNAL | Ground / signal return |
Notes
- Power pins (1, 4) are longer so power mates before data on insertion.
- USB 3.0 Standard-A adds 5 SuperSpeed pins in a recessed second row.
Reference: USB-IF / Wikipedia - USB hardware· verified 2026-06-27