Work out egress cost instantly with clear inputs, formula shown and shareable results.
Egress is the most expensive commodity in cloud pricing at around nine cents per gigabyte, roughly a hundred times the cost of storing the same data for a month. A CDN reduces origin egress by its hit ratio and usually charges less per gigabyte itself, so at 80 percent offload the origin bill falls to a fifth even before the CDN's own lower rate is considered.
Egress cost
origin GB = total GB x (1 - CDN offload); billable = origin GB - free allowance; cost = billable x price per GB
It is priced strategically rather than by cost. Ingress is free, which makes moving data in easy and moving it out costly — the basis of the data gravity concern.
It is billed separately and usually at a cent or two per gigabyte in each direction. Chatty microservices spread across zones can generate a surprisingly large bill.