STP cost long mode

STP uses two methods for calculating link costs. Costs conforming to long mode have the following values:

Data rateSTP cost
4 Mbps5000000
10 Mbps2000000
16 Mbps1250000
100 Mbps200000
1 Gbps20000
2 Gbps10000
10 Gbps2000
100 Gbps200
1 Tbps20

These values are based on the updated IEEE 802.1t standard.

For short mode STP costs, take a look at STP cost short mode

Links:

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4000/8-2glx/configuration/guide/spantree.html#wp1193557