https://laurentdumont.github.io/aws-network-cost-helper/

What is this?

• AWS will bill you for bandwidth in many different directions.
• This can be a shock from on-prem where bandwidth/network is absorbed as part of the overall infrastructure.
• The AWS calculator makes it a bit hard to visualize the flows and direction of traffic.
• We need to find a way to educate and upskill architecture and service team.
• Network traffic is well suited to a visual representation.

Scenario

• Inter availability-zone traffic between EC2 instances in the same region.
• Traffic towards a private link towards a third party vendor (not an AWS service).

Traffic cost breakdown

Traffic pattern	Cost
Inter region traffic	0.01 USD Per GB Inbound 0.01 USD Per GB Oubound
Inter AZ traffic	0.01 USD Per GB Inbound 0.01 USD Per GB Oubound
Traffic over a TGW between two VPC	0.02 USD per GB for each attachment Traffic coming into the VPC Traffic coming out of the VPC
Traffic over a Direct Connect	0.02 USD per GB OUT (from AWS to on-premise)
Traffic over a Private Link endpoint	0.01 USD per GB (IN + OUT)
Traffic over a NAT Gateway	0.045 USD per GB (IN + OUT)
Traffic over a Load Balancer (ALB, NLB)	Total processed bytes: 100 GB per month x 0.00136986 months in an hour = 0.136986 GB per hour 0.136986 GB per hour / 1 GB per hour for EC2 instances, containers and IP addresses as targets. = 0.136986 Processed bytes LCUs 100 new connections / 600 new connections per LCU = 0.16666666666666666 new connections/flows LCUs 100 new connections x 5 seconds = 500 active GWLB connections 500 active connections / 60000 connections per LCU = 0.008333333333333333 active GWLB connections LCUs Max (0.136986 processed bytes LCUs, 0.16666666666666666 new connections/flows LCUs, 0.008333333333333333 active connections/flows LCUs) = 0.16666666666666666 max GWLB LCUs 0.16666666666666666 GWLB LCUs x 0.004 GWLB LCU price x 730 hours per month = 0.49 USD (Gateway Load Balancer LCU usage) Total LCU charges for all Gateway Load Balancers (monthly): 0.49 USD
Traffic to an AWS API with PublicVIF from on-premise	0.01 USD Per GB Oubound (from AWS to on-premise)
Traffic to an AWS API with Private Endpoint from on-premise	0.01 USD per GB (IN + OUT)
Traffic over VPC peering between regions	0.01 USD Per GB Inbound 0.01 USD Per GB Oubound
Traffic over VPC peering in the same region	Traffic between resources in the same AZ is free 0.01 USD Per GB Oubound