NAT Gateway Calculator
Estimate your monthly AWS NAT Gateway bill. It's usually higher than you think.
Usually 1 per Availability Zone (e.g., 3 for HA).
Total traffic passing through NAT (outbound to internet).
Assumptions (us-east-1)
💡 Pro Tip
ClusterCost can show you exactly which pods are sending traffic to the internet, helping you identify why your processing fees are high.
How to Use This Calculator
- Enter NAT Gateway Count: For high availability, most teams run 1 NAT Gateway per Availability Zone (typically 3 AZs = 3 gateways).
- Estimate Data Processed: Check your CloudWatch metrics for
BytesOutToDestination. This is the total outbound traffic to the internet. - Review the Breakdown: The calculator shows Fixed (hourly) and Variable (processing) costs separately so you can see which is driving your bill.
Common NAT Gateway Scenarios
Dev/Staging
Single-AZ, light traffic
Production HA
3 AZs, moderate traffic
Data-Heavy
High egress (video/ML)
Understanding Your NAT Gateway Costs
AWS charges for NAT Gateways in two dimensions:
Hourly Fees (Fixed)
$0.045/hour per NAT Gateway
This is a flat rate charged for every hour the NAT Gateway exists, regardless of traffic. For 3 gateways running 24/7, expect ~$100/month.
Processing Fees (Variable)
$0.045/GB processed
Charged for every GB of data that flows through the gateway. This is where costs explode for data-intensive apps like video streaming or ML inference.
Frequently Asked Questions
How much does a NAT Gateway cost per month?
A single NAT Gateway costs approximately $32.85/month in hourly fees alone (730 hours × $0.045). Add data processing fees on top: for 1TB of traffic, that's an additional $45, bringing the total to ~$78/month per gateway.
Why is my NAT Gateway bill so high?
The most common culprits are: (1) Docker image pulls from public registries, (2) API calls to 3rd-party services, and (3) Log/metrics egress to external monitoring tools. Use VPC Endpoints for S3/DynamoDB to bypass NAT entirely.
What is the data processing fee?
AWS charges $0.045 per GB for data that passes through the NAT Gateway. This is in addition to standard internet egress fees ($0.09/GB). So for 1GB leaving AWS, you might pay $0.01 (cross-AZ) + $0.045 (NAT) + $0.09 (egress) = $0.145 total.
Can I avoid NAT Gateway costs?
Yes. Use VPC Gateway Endpoints (free) for S3 and DynamoDB. Move non-sensitive workloads to public subnets so they use the Internet Gateway (no processing fee). For advanced users, consider NAT Instances (self-managed EC2) or IPv6-only networking.