google_compute_network cost estimation

A google_compute_network is the global VPC that your Compute Engine VMs, GKE clusters, and load balancers attach to. Creating the network is free, and so is the scaffolding around it: subnetworks, routes, firewall rules, and internal IP addressing. GCP does not charge for the VPC itself, and unlike AWS a VPC in GCP is global, so a single network spans every region without a per-region fee.

The cost lives in what runs inside the network and what crosses its edge. Egress to the internet is billed per GB and tiered by destination, egress between regions is billed per GB, and even traffic between zones in the same region carries a small per-GB charge. Cloud NAT (google_compute_router_nat) is the usual paid gateway for private VMs reaching the internet, adding an hourly gateway charge plus per-GB data processing. VPC Network Peering is free to set up but the cross-region and cross-zone transfer over it still bills.

The high-value decisions are architectural: how much traffic leaves the network versus staying internal, whether chatty services sit in the same zone to avoid inter-zone charges, and how many Cloud NAT gateways you provision. c3x prices the NAT gateways, VMs, and egress driven by a network and treats the VPC, its subnets, and routes as the free scaffolding they are.

Terraform example

A minimal but realistic configuration that C3X can estimate.

resource "google_compute_network" "main" {
  name                    = "main-vpc"
  auto_create_subnetworks = false
  routing_mode            = "REGIONAL"
}

Pricing dimensions

What you actually pay for when you provision google_compute_network.

Dimension	Unit	What's being charged
VPC network and routes	free	The network, subnetworks, routes, firewall rules, and internal IPs have no charge. $0
Internet egress	per GB	Bytes leaving Google's network to the public internet. First 200 GB/month free at the project level, then tiered by destination. ~$0.12/GB to most destinations (Premium tier)
Inter-region and inter-zone egress	per GB	Traffic between GCP regions, and between zones within a region, generated by resources on the network. Inter-zone: $0.01/GB
Cloud NAT (typical inside)	per hour + per GB	The common paid gateway for private VMs to reach the internet, provisioned via google_compute_router_nat. ~$0.044/gateway-hour + $0.045/GB

Optimization tips

Common ways to reduce google_compute_network cost without changing the workload.

Keep traffic internal and in-zone

Internal traffic within a single zone is free. Colocating chatty services in one zone avoids the per-GB inter-zone charge, and keeping data in-region avoids inter-region egress.

Use Private Google Access instead of NAT for Google APIs

Removes NAT processing on Google API calls

Private Google Access lets private VMs reach Google APIs and services without a Cloud NAT gateway, removing NAT data-processing charges on that traffic.

Right-size Cloud NAT gateways

One Cloud NAT per region covers all subnets in that region. Consolidating avoids paying multiple gateway-hour charges for the same egress.

FAQ

Does a GCP VPC network cost money?

No. The VPC network, its subnetworks, routes, and firewall rules are free. Cost comes from resources inside it and traffic that leaves it: internet egress, inter-region and inter-zone transfer, and Cloud NAT.

Is a GCP VPC per-region like an AWS VPC?

No. A GCP VPC is a global resource. One network spans every region with no per-region fee, and subnetworks are the regional pieces inside it.

What is usually the biggest cost tied to a VPC?

Egress. Internet egress is tiered per GB after the first 200 GB/month free, and inter-region and inter-zone transfer add per-GB charges. Cloud NAT adds a gateway-hour plus per-GB processing charge for private VMs reaching the internet.