There have been many posts on the Internet explaining how EIGRP gets its composite metric. I’ve been running around searching for information and it seems that there are NOT that many people who seem to post this info. Here it is, the real calculation method for EIGRP metrics.

Everyone says EIGRP metric is based off bandwidth (BW) and delay (DLY), which are values determined “per-interface” as shown below in bold:

EIGRP Algorithm / Formula:
Composite Metric = 256 * ([K1 * BW + K2 * BW/(256-Load) + K3 * DLY] * [K5/(RELY + K4)])

Default EIGRP K-Values are K1=1, K2=0, K3=1, K4=0, K5=0.  To modify the or change the K values for calculation to include the other non-default variables you input the command below:

What they don’t really emphasize and its important for the formula!

The bandwidth (BW) and delay (DLY) values are based on a “scaled average”.

Bandwidth for EIGRP = (10⁷ / Interface Bandwidth)
Delay for EIGRP = (Interface Delay in usec / 10)

So the formula ends up being Metric = 256( (10,000,000/ BW) + (DELAY/10)).
To modify any EIGRP K-values to use more variables, enter command shown below:

CRNARVSDRR02(config-router)#metric weights ?
<0-8>  Type Of Service (Only TOS 0 supported)

CRNARVSDRR02(config-router)#metric weights 0 ?
<0-255>  K1

CRNARVSDRR02(config-router)#metric weights 0 1 ?
<0-255>  K2

CRNARVSDRR02(config-router)#metric weights 0 1 0 ?
<0-255>  K3

CRNARVSDRR02(config-router)#metric weights 0 1 0 1 ?
<0-255>  K4

CRNARVSDRR02(config-router)#metric weights 0 1 0 1 0 ?
<0-255>  K5

CRNARVSDRR02(config-router)#metric weights 0 1 0 1 0 0 ?
<cr>

CRNARVSDRR02(config-router)#metric weights 0 1 0 1 0 0