Enter the size of the data packet and bandwidth of the network into the calculator to determine the transmission delay.

Transmission Delay Formula

The following formula is used to calculate a transmission delay: 

 TD = S / B
  • Where TD is the transmission delay
  • S is the size of the data packet
  • B is the bandwidth of the network the packet is being sent over

To calculate a transmission delay, divide the size of the data packet by the bandwidth of the network.

Transmission Delay Definition

What is a transmission delay?

A transmission delay is a measure of the time it takes to put a data packet onto a transmission link.

Transmission delay is also commonly referred to as store-and-forward delay or packetization delay because, in essence, it’s the time it takes for a packet to be pushed onto a wire.

Example Problem

How to calculate transmission delay?

The following example problem will outline the steps and information required in order to calculate a transmission delay.

First, determine the total size of the packet that is being transferred over the network. In this case, the packet will be said to be 50 bits. This is not typical, but it will help make the calculation more simple.

Next, determine the bandwidth of the network that is transferring the packet. In this example, the network has a bandwidth of 20 bits per second, and the transmission is using all of the bandwidth.

Finally, calculate the transmission delay using the formula above:

TD = S / B

TD = 50/20

TD = 2.5 seconds