VNC vs. Software KVM

VNC and KVM software can both be used to remote control a computer.

However, there are some significant differences between both program types:

How VNC works

VNC remotely logs onto the remote computer and transmits the complete desktop contents of that PC over the network.

You see the desktop of the remote computer in a program window on your main computer:


You can control the remote computer within this window.

The remote computer actually doesn't need any monitor as its desktop is displayed on the main computer anyway.

Benefits of VNC

  • The remote computer can be located off-site, even in a different country as VNC works over the internet.
  • VNC allows you to control a 'headless' computer as it transmits the monitor contents to the main computer's desktop.

VNC limitations

  • VNC transmit the desktop contents over the network, affecting network bandwidth. This can cause noticeable screen refresh lag. VNC isn't designed for applications with fast graphics activity on the remote computer (games, graphics software, CAD applications, etc).
  • The desktop contents is treated with image compression before it is transmitted over the network, leading to to loss of screen quality and false colors. VNC is not suitable for any application that rely on accurate display quality.
  • The remote computers desktop dimension may not exceed the desktop dimensions of the main computer. Otherwise, the VNC contents will be scaled to fit on the main computer's monitor.
  • VNC applications may not support multiple monitors on the remote computers.
  • While controlling a remote computer, the main computer's desktop real estate is occupied with displaying the VNC, leaving less space left for other program windows on the main computer. You can either watch the VNC or the local desktop but barely both at the same time.

How a KVM Software works

With a Software KVM, you move the mouse into the direction of the remote computer you wish to control. Once, you reach the border of your main computer, the mouse cursor jumps onto the remote computer:


The Software KVM only transmit the current mouse cursor position and keyboard input to the remote PC, which is very little data. No desktop contents is transmitted.

While you control the remote computer you look onto its monitor, so all computers need their own monitor.

Limitations of a Software KVM

  • Software KVMs can't be used over the internet as the monitor of the remote computer needs to be visually accessible.
  • No desktop screen contents is transmitted to the main PC. Each computer needs its own monitor.

Benefits of a Software KVM

  • A KVM Software does only require very little network bandwidth and is much snappier than VNC.
  • The display quality is uncompromised as you look onto the original monitor of the remote computer.
  • Unrestricted access to both desktops of the main and remote computer while controlling the remote computer. No VNC occupies space on your main computer monitor.
  • Powerful Software KVMs such as ShareMouse offers support for up to nine computers.
  • Seamless and intuitive switching between computers with swipe of your mouse. No manual authorization is required.


VNCSoftware KVM
Internet support

VNC works over the internet.

All computer must be local.

Support for headless computer

Remote computers don't need a monitor.

Each computer needs its own monitor.

Network load

High network load

Almost no network load


The desktop is displayed with lag.

No lag.

Display quality

Compression artifacts, color variation due to image compression.

No compromise.

Switching speed

Slow. Requires retrieving the VNC window first.

Instantly by moving the mouse.

Desktop Real Estate

The main monitor is mostly occupied by the VNC window.

Each monitor shows the original desktop of each PC.

Multi Monitor support

Main monitor dimensions must exceed the remote computer's dimensions.

Unrestricted multi monitor support.

Support for multiple computers

Awkward. VNC has not been designed for quick access to multiple computers.

Seamless support for up to nine computers.


A VNC application is suitable if you want to remote control a computer which has no own monitor of if the remote computer is not near your desk. If this is what you are looking for, we recommend to check out

A Software KVM is your ultimate choice if you have two or more computers with their own monitors on your desk.

Please check out ShareMouse, a very powerful and easy-to-use Software KVM solution.