AWS Cost Calculators
10 free tools · no login · nothing uploaded
Most AWS cost calculators multiply a rate by a quantity and stop. That is fine for a budget estimate and useless for a decision, because the charges that actually surprise people are the ones that stack, survive an optimisation, or apply to something you were not thinking about.
A NAT gateway bills hours whether or not traffic flows, then bills per GB, and then internet-bound bytes pay data transfer out on top — three charges on one line item. Stopping an idle EC2 instance stops the instance charge and leaves the EBS volumes billing at full rate, while starting an Elastic IP charge you did not previously have. Turning on RDS Multi-AZ doubles the storage bill as well as the compute bill, and on a large database the storage half is the bigger surprise. Migrating a big gp2 volume to gp3 saves 20% on storage right up until you buy back the IOPS that gp2 was giving you for free.
Every calculator here charges those things, states the rate it used and the date that rate was read off a vendor source, and lists where the model is deliberately conservative. The numbers usually come in lower than the ones you will see elsewhere, and that is the point — a savings figure you cannot defend in a review is worse than no figure at all.
All prices are US East (N. Virginia) list prices, before any negotiated or committed-use discount. Everything runs in your browser.
10 tools in aws savings calculators
NAT Gateway & Data Transfer Calculator
Price the line item that surprises everyone, and find the cheaper shape.
Model NAT gateway hours, per-GB processing, internet egress tiers and cross-AZ chatter together — then see what VPC endpoints, an AZ-local topology, or simply deleting an idle gateway would save.
EBS gp2 vs gp3 Calculator
The easiest 20% in AWS — unless your volume needs paid IOPS.
Compare gp2 against gp3 on your real volume sizes, including the paid IOPS and throughput gp3 needs to match a large gp2 volume. Most migrations save 20%; the ones that do not are the reason this does the arithmetic properly.
S3 Storage Class Calculator
Where the break-even really is, once transitions and minimums are counted.
Compare S3 Standard, Infrequent Access, One Zone-IA, Glacier Instant and Glacier Flexible on your object count, size and access rate — with transition requests, retrieval fees, minimum durations and the 128 KB floor all charged.
EC2 Idle & Rightsizing Calculator
What idle instances cost, and what stopping them actually saves.
Price idle and oversized EC2 capacity, then compare the three fixes: schedule it off, size it down, or commit. Counts the EBS volumes and Elastic IPs that keep billing after you stop an instance — the reason stopping saves less than expected.
RDS Cost & Rightsizing Calculator
Multi-AZ doubles more than you think. Price it before you enable it.
Model RDS instance hours, storage, Multi-AZ, and Graviton against your current setup — with the storage doubling Multi-AZ causes shown separately from the compute doubling, because only one of them is negotiable.
Lambda Cost & Memory Tuning Calculator
The cheapest memory setting, and the fastest one that costs the same.
Price Lambda invocations and duration across every memory setting, including the free tier and Arm. Because CPU is allocated in proportion to memory, the cheapest configuration and the fastest affordable one are rarely the same number.
Fargate vs EC2 Calculator
Per vCPU Fargate looks dear. Per cluster it often is not.
Compare Fargate against the EC2 capacity you would actually have to buy — whole instances, agent overhead, deploy headroom, and the hours a cluster runs when the tasks do not. The per-vCPU comparison everyone makes is the misleading one.
DynamoDB On-Demand vs Provisioned
The break-even is a utilisation, not a traffic level.
Model both capacity modes on your real traffic shape. Provisioned is ~3.5x cheaper per request and bills every hour whether traffic arrives or not — so the decision turns on how peaky your traffic is, not how large it is.
ElastiCache Cost & Reserved Nodes
Replicas are nodes. Cross-AZ replication is a bill.
Price a Redis or Valkey cluster including the replica multiplier and the cross-AZ replication traffic nobody counts, then compare all four reserved-node terms — which are real published rates here, not an indicative band.
CloudFront vs S3 Direct Calculator
Object size decides this, not cache hit rate.
Compare serving through CloudFront against serving straight from S3. The CDN is cheaper per byte and 2.5x dearer per request, so the answer turns on your average object size — and the crossover is around 200 KB.
Other categories
Six calculators, or one platform watching every account.
These price a snapshot you type in. Finitizer inventories every volume, instance, gateway and function across every account, checks actual utilisation rather than provisioned, and opens the change as a Terraform pull request.