CH340 driver for Windows
The CH340 driver comes from the chip maker, WCH (Nanjing Qinheng), at wch-ic.com. Download CH341SER.EXE, which covers CH340 and CH341 chips on Windows 11, 10, 8.1 and older. It is a one-key installer that is Microsoft WHQL certified. After it runs, the board appears as a COM port.
Checked October 30, 2026 against the manufacturer's own pages.
Driver downloads
| Driver | Version | Released | Size | Windows | Download |
|---|---|---|---|---|---|
| CH341SER.EXE (CH340/CH341 USB to serial driver) | 4.0 | June 24, 2026 | 780KB | Windows 11 down to 98, 32-bit and 64-bit | Download from wch-ic.com |
Values copied from the manufacturer's page on October 30, 2026. The file always downloads from the manufacturer, never from this site.
Hardware IDs on this page
| Hardware ID | Device name |
|---|---|
USB\VID_1A86&PID_7523 | CH340 serial converter |
USB\VID_1A86&PID_7522 | CH340 serial converter |
USB\VID_1A86&PID_5523 | CH341 in serial mode, usb to serial port converter |
USB\VID_1A86&PID_7584 | CH340S |
Match the first line of Hardware Ids in Device Manager (Properties, Details) against this list. Names come from the public PCI ID Repository.
The short version
What to install and where it comes from. Every link goes to the manufacturer or Microsoft, never to a copy.
Official files only, nothing bundled
Step by step
Check the chip ID
Plug the board in. In Device Manager look under Other devices or Ports for USB Serial or USB-SERIAL CH340. In Properties, Details, Hardware Ids, a line with VID_1A86 confirms a QinHeng chip.
Download from WCH only
Open the CH341SER.EXE page at wch-ic.com and press Download. The file is small, about 780KB.
Run the installer
Start CH341SER.EXE as administrator and press INSTALL. Wait for the message that the driver installed, then close it.
Replug the board
Unplug the USB cable and plug it in again, ideally with a data cable, not a charge-only lead. A new entry such as USB-SERIAL CH340 (COM3) should show under Ports.
Pick the port in your tool
In the Arduino IDE or your terminal program, select the new COM number. Set the baud rate your sketch uses.
What the CH340 is
The CH340 is a small chip from WCH, a Chinese maker also known as Nanjing Qinheng Microelectronics. It turns USB into a serial port. You find it on low-cost Arduino-style boards, ESP8266 and ESP32 development kits and many hobby tools. In the public USB ID list, the vendor code is 1A86, and the usual product code is 7523.
The same company sells the CH341. That chip can do serial and also other modes, such as an I2C or parallel adapter. The 5523 product code is the CH341 in serial mode. WCH’s driver page says the Windows package covers both chip families.
What the maker’s page says
On WCH’s own page, the Windows driver is CH341SER.EXE, version 4.0, updated 2026-06-24, size 780KB. It is a one-key install package and the description says it is Microsoft WHQL or HCK certified. It lists the supported chips, among them CH340G, CH340T, CH340C, CH340N, CH340K, CH340E, CH340B and several CH341 parts. The same page offers a ZIP version and drivers for Linux, macOS and Android.
The most common problem
The board is detected but there is no COM port, or the port shows a yellow warning. The first cause is a cable that carries only power. Swap it for a known data cable. The second cause is a driver that did not finish. Run the installer again, press UNINSTALL first if the old one is damaged, then INSTALL, and replug. If the COM number clashes with another device, open the port’s Properties, Port Settings, Advanced and choose a free number.
Do not disable driver signature checks to force an install. The current package is signed, so there is no need.
Questions
Is the CH340 driver safe?
Take it only from wch-ic.com, the maker's site. The installer there is described as Microsoft WHQL certified. Avoid copies on download portals.
No COM port appears after install.
Try a different cable first. Many cables carry power only. Then try another USB port and replug the board.
Does Windows already include a CH340 driver?
Windows Update can supply one for some chips. If your board already shows a COM port, you do not need the installer.
Does the same installer cover CH341?
Yes. WCH lists CH340G, CH340C, CH340N, CH341A and others as covered by this package.