Quick wins for a faster PC:
Repair Windows errors before they cause bigger problemsFix Now →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →The right Windows virtual COM port software depends on what needs connecting: two local applications, a physical serial port and another endpoint, or a remote serial device over a network. For a local software-to-software link, use a virtual null-modem pair such as com0com or a configurable commercial tool. For remote hardware, use software designed for serial-over-network access. If you only need an existing local port inside a Remote Desktop session, Windows’ RDP redirection is a different option—not a way to create an arbitrary local COM pair.
First identify what the virtual COM port needs to connect
“Virtual COM port software” covers several different arrangements. A virtual port may be one endpoint in a local pair, a route between ports, or a Windows-facing connection to serial hardware elsewhere on a network. Choosing by topology prevents a common mismatch: installing a pair emulator when the target is remote hardware, or expecting RDP redirection to create a local pair.
As an Amazon Associate I earn from qualifying purchases.
- Two local programs: create a virtual null-modem pair. Each program opens one end of the pair.
- Local port routing or sharing: choose a product whose documented features include the specific real-to-virtual forwarding or port management you need.
- Serial hardware on a network: use a serial-over-network solution that supports the target hardware and presents a COM port to the Windows application.
- An existing local port in a remote desktop session: configure Remote Desktop serial redirection, if the client and session environment support it.
A USB-to-RS-232 adapter can supply a physical serial connection to a PC without a serial connector, but it does not create a virtual pair. Adapter drivers and compatibility with the hardware still matter.
Free tools Windows power users keep installed
One-click scans. No signup required.
Windows virtual COM port software compared
| Option | Best fit | What its source documents | Check before deployment |
|---|---|---|---|
| com0com | Free, open-source local virtual null-modem pair | The project describes a GPL-licensed kernel-mode emulator for connecting two COM-port applications or connecting an application to a device emulator. com0com project | Current Windows release support, driver signing and installation behavior, and COM naming requirements. |
| Eltima Virtual Serial Port Driver | Configurable local pairs and port routing | The vendor lists virtual pairs, serial settings and control-line support, and forwarding between real and virtual ports. Its page lists a 14-day fully functional trial and a starting price of $89.95. Product page | Edition-specific features, current price, Windows and architecture compatibility, driver requirements, and licensing. |
| HW VSP3 | Presenting supported remote serial hardware as a Windows COM port | HW group describes TCP/IP redirection to a remote hardware interface. Its catalog lists Windows 8, Windows 10, and Windows Server 2016 support for Single mode; Multi mode is described as supporting up to 254 remote serial ports, limited to HW group products. HW VSP3 catalog | Current Windows support, exact device compatibility, and whether Single or Multi mode suits the setup. |
| Eltima Serial Port Redirector | Remote serial access through supported network or session protocols | The vendor lists TCP, UDP, RDP, and Citrix support, a 14-day trial, and a starting price of $259.95. Its page reports version 9.0.1288, released 13 May 2026. Product page | Current version and price, the exact supported protocol and configuration, licensing, and network exposure. |
| Microsoft RDP serial redirection | Using an existing local serial port in an Azure Virtual Desktop session | Microsoft documents configuring serial/COM port redirection over RDP. Microsoft Learn | Local port availability and the client, session, and host-pool configuration. This is not arbitrary local pair creation. |
How do I connect two programs through virtual serial ports?
Use a null-modem pair when both programs run on the same Windows computer and each expects to open a COM port. The pair provides the connection between the two software endpoints; it does not simulate the device protocol that either program expects. If one endpoint must behave like a particular instrument or controller, you also need a suitable device-emulation program or other protocol implementation.
#1 Best Overall
- !!Please NOTE: this is MALE RS232 to DB9 SERIAL CABLE ,Not VGA!!!It is 9 pin, NOT 15 pin!! Look carefully of the Pin is match with your device. Before ordering , please confirm the interface gender is waht you need. After receiving ,please read user manual /instruction at first and download the Driver at first from FT232 Official website or Cisco website . Customer service always online.
- Wide range of applications: USB to RS232 DB9 male serial adapter can work with your Windows (10 / 8.1 / 8 / 7 / Vista / XP), MAC or Linux system and other platforms. USB adapter is designed to connect to serial devices, such as serial modem with DB9, ISDN terminal adapter, digital camera, label writer, palm computer, barcode scanner, PDA, cash register, CNC, PLC controller, tax printer, POS, bar code scanner, label printer, etc
- High quality: ftdi usb serial,the latest ftdi chip set ensures more reliable and faster operation. USB 2.0 to RS232 male DB9 console cable will support 1Mbps date transfer rate.
- Most convenient: rs232 to usb simple installation, plug and play, COM port creation, baud rate can be changed to the required settings. USB power supply - no external power supply required.
- Exquisite design: usb-to-serial,Gold Plated USB RS232 connector and PVC cable ensure high performance and extra durability. Powered by USB port, this USB to DB9 series RS232 adapter cable is designed to fit easily into your handbag.
com0com for a focused local pair
com0com describes itself as an open-source, GPL-licensed kernel-mode null-modem emulator. Its stated use is to connect two COM-port applications, or connect one application to a device-emulation program. The project information cited here does not establish current Windows 11 compatibility, recent release status, or an independent security review, so check current release and installation information before relying on it.
Eltima Virtual Serial Port Driver for additional configuration
Eltima says its Virtual Serial Port Driver creates virtual COM pairs recognized by applications and documents serial-setting emulation, control-line support, and forwarding between real and virtual ports. The vendor lists support for Windows 7, 8, 8.1, 10, and 11 (32- and 64-bit), Windows Server 2012, 2016, 2019, and 2022, and Windows on ARM. The same page identifies version 11.0.1096, released 3 August 2026, a 14-day fully functional trial, and a starting price of $89.95. These are vendor-published, time-sensitive details; confirm current availability, price, and the features included in the edition you need. Check the vendor’s product information.
Rank #2
- [ USB to RS-232 Serial Adapter ] : 5ft Cable Length - Easily connect legacy DB-9 serial devices to modern USB-equipped computers. Uses include industrial, lab, and point-of-sale applications.
- [ Easy Testing ] : Built-in signal tester features full LED indicators with dual-color display for quick and easy testing of RS-232 host-to-device connections.
- [ Wide Compatibility ] : Built with an FTDI Chipset. Works seamlessly with Windows 7, 8, 10, 11, Linux, and macOS 10.X, making it a highly versatile solution across platforms.
- [ Why Gearmo? ] : Your trusted partner based in the USA, providing advanced engineering, highly reliable and superior built products to handle the most demanding industries for over 10 years.
- [ Engineering Support ] : Need specs? Contact us for CAD files, mechanical drawings, or datasheets to support your integration or project needs.
The product page describes signal lines including DTR, DSR, CTS, RTS, DCD, and RI, as well as strict baud-rate emulation; edition differences apply. Verify that the particular application and device rely on the same signals and serial behavior before selecting an edition.
The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →How can I access a serial device over Ethernet as a COM port?
Choose a serial-over-network tool that can communicate with the remote serial interface and expose the connection in the form the Windows application expects. The remote endpoint, network protocol, and software’s hardware support must all match; a local null-modem pair alone does not connect to remote equipment.
Rank #3
- Serial adapter allows a serial device to be connected to a USB computer
- Plug and play convenience:DB9 serial port is seen as a COM port by your computer, and is available for use by any program that accesses COM ports
- No need for an external power adapter:draws power directly from your computer via the USB connection
- DB9 serial port supports data transfer rates up to 230 Kbps:twice the speed of a standard built in serial port
- LED shows adapter status and data activity at a glance
HW VSP3 for supported HW group interfaces
HW group’s catalog describes HW VSP3 as adding a Windows virtual serial port, such as COM5, and redirecting traffic over TCP/IP to a specified remote hardware interface. The catalog lists Windows 8, Windows 10, and Windows Server 2016 support for HW VSP3 Single. Its Multi mode is described as handling up to 254 remote serial ports and supporting HW group products only. That port count is a vendor-stated limit for this mode, not a general Windows limit. The catalog does not establish Windows 11 support, so confirm current compatibility and the exact device with HW group. See HW group’s HW VSP3 catalog.
Eltima Serial Port Redirector for listed network and session protocols
Eltima lists TCP, UDP, RDP, and Citrix support for its Serial Port Redirector. Its product page reports version 9.0.1288, released 13 May 2026, a 14-day trial, and a starting price of $259.95. These are vendor-stated product details, not independent performance findings. Verify that the protocol and connection mode match the remote device and application, and review network exposure and licensing. Check the product page for current details.
Rank #4
- MAXIMIZED PORTABILITY: This USB to serial RS232 adapter converts a USB port into an RS232 DB9 serial port; Compatible with barcode readers/scanners, networks switches, receipt printers, PLCs, medical devices, oscilloscopes, scales, etc.
- BROAD COMPATIBILITY: Compatible with your USB 1.0, 2.0 or 3.0 ports, this USB-A to RS232 converter works with your Windows, MacOS or Linux system
- PORTABLE DESIGN: ?Powered by a USB port, this USB to RS232 serial adapter cable?features a lightweight design?that conveniently fits into your carrying case, making it ideal for professionals on the go
- USB TO SERIAL ADAPTER SPECS: 17in (43cm) Cable Length | Max Baud 921.6 Kbps | 512 Byte FIFO | Supports Windows, macOS, and Linux | Prolific PL2303GT Chipset | Odd, Even, Mark, Space, or None Parity Modes | 5/6/7/8 Data Bits
- THE IT PRO'S CHOICE: Designed and built for IT Professionals, this USB to serial converter cable is backed for 3-years, including free lifetime 24/5 multi-lingual technical assistance
Does Windows 11 have virtual COM ports built in?
The Microsoft documentation cited here covers serial/COM port redirection over RDP for Azure Virtual Desktop; it does not describe a general Windows feature for creating arbitrary local virtual COM pairs. Do not treat Remote Desktop redirection as a substitute for a null-modem emulator or a serial-over-IP bridge. For any third-party driver, verify support for the exact Windows release, CPU architecture, driver-signing policy, and installation restrictions on the target PC. Microsoft’s configuration documentation.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
Which virtual COM port software works with my serial device?
Start with the connection path, then verify serial behavior—not just whether the software can create a COM name. A successful connection can still fail if the device expects different handshaking, baud-rate behavior, port naming, or a particular hardware interface.
Best Value
- Gold Plated USB 2.0 to RS232 Female DB9 Serial Cable connects serial DB9 (9 PIN) devices such as modems to standard computer USB ports, supporting up to 1Mbps data transfer rate. [ IMPORTANT NOTE ]: This USB to RS232 adapter features a female RS232 connector, NOT male — please confirm your device’s serial port type before purchase
- Adopted with latest Prolific PL2303 chipset, this USB to RS232 adapter supports Windows 11/10/8.1/8/7, Linux and Mac OS. Windows 11/10/8.1/8/7 is plug-and-play and will be automatically identified as COM port. Windows built-in drivers match most USB-to-serial chips; it will automatically download and install the matched driver under network environment. For offline Windows, Mac OS and most Linux systems, please download and install the official driver from CableCreation official website. Ubuntu Linux supports plug and play without driver installation
- Widely compatible with modems, ISDN terminal adapters, digital cameras, label writers, palm PCs, PDAs, cash registers, CNC, PLC controllers, tax printers, POS machines, barcode scanners, and other devices with standard DB9 serial ports. Please be noted this USB to RS232 female DB9 serial converter cable is NOT compatible with cutting plotter and SCM equipment. Kindly confirm your device interface and model before placing an order
- Features tinned copper conductor and triple shielding to ensure stable and high-quality data transmission. USB bus-powered design requires no external power adapter. If your computer cannot recognize the cable normally, please match it with a null modem adapter for normal use
- CableCreation provides 24-month warranty and lifetime professional customer service. This 6.6ft USB 2.0 to RS232 Female DB9 serial converter cable follows standard pin definition, suitable for the device requiring female RS232 interface. If you encounter any problems of driver installation or device compatibility, please contact our customer service at any time, and we will assist you within 24 hours
- For local software testing: confirm that both applications can open the paired COM ports and that the emulator or device software supplies the protocol behavior the application expects.
- For a physical serial device connected locally: check the hardware connector and serial standard, the adapter chipset and driver if using USB, and whether the software’s real-port routing features match the workflow.
- For a remote serial device: verify that the tool supports the exact remote interface and protocol, and that network configuration allows the required traffic.
- For control-sensitive equipment: check required lines such as RTS/CTS or DTR/DSR, as well as baud-rate and other serial settings.
- For managed or production PCs: confirm driver signing and installation policy, support for the Windows release and CPU architecture, port naming constraints, license terms, and support availability.
No independent comparative benchmark or reliability study is established by the cited sources. Product capabilities, compatibility lists, release details, and prices above are vendor or project statements; they do not establish that one option is universally the most reliable or compatible.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
