Split Azure Firewall cost into its fixed hourly deployment fee and the per-GB data processing charge.
Azure Firewall has two meters: a fixed hourly deployment fee per firewall instance and a per-GB data processing fee. Because the fixed fee dominates at low volume, the blended cost per GB collapses as you consolidate traffic — one firewall in a hub inspecting all spokes is far cheaper per GB than a firewall in each spoke. The fixed fee is roughly $900 a month per deployment before a single packet is inspected, so idle development firewalls are pure waste and deallocating them overnight is a genuine saving; confirm the Basic, Standard and Premium rates for your region in the Azure pricing calculator.
Azure Firewall
monthly = deployments × hourly rate × 730 + data processed × per-GB rate; blended cost per GB = total ÷ GB processed.
monthly = deployments × hourly rate × 730 + data processed × per-GB rate; blended cost per GB = total ÷ GB processed. Azure Firewall has two meters: a fixed hourly deployment fee per firewall instance and a per-GB data processing fee. Because the fixed fee dominates at low volume, the blended cost per GB collapses as you consolidate traffic — one firewall in a hub inspecting all spokes is far cheaper per GB than a firewall in each spoke.
The fixed fee is roughly $900 a month per deployment before a single packet is inspected, so idle development firewalls are pure waste and deallocating them overnight is a genuine saving; confirm the Basic, Standard and Premium rates for your region in the Azure pricing calculator.
This calculator takes 6 inputs: Firewall deployments, Deployment rate, Data processed, Price per GB processed, Billed hours per month, Hours the firewall sits idle. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.