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Tools

Every free CostMon tool, in one place

Twenty-four calculators and reference tools for cloud and AI spend, built to answer one question at a time. Pick the one that matches what's in front of you.

Every tool on this page runs entirely in your browser. Nothing you type or upload is sent anywhere — there's no backend for it to go to — and there's no signup to use any of them.

You already have a bill in hand

Tools that read your real numbers instead of asking you to estimate.

AWSReads your export

AWS Bill Analyzer

Drop in a Cost Explorer CSV and see where the money went last month.

You bring
An AWS Cost Explorer CSV export
You get
A cost breakdown, period-over-period movers, and a run-rate projection. Nothing leaves your browser.
Reference

AWS Bill Decoder

Look up a cryptic AWS line item and find out what it means and why it showed up.

You bring
One confusing line item from your bill, like NatGateway-Bytes
You get
A plain-English explanation, why it tends to spike, and how to cut it
AWS

AWS Data Transfer & Egress Cost Calculator

Price out internet egress, cross-AZ, NAT gateway, and inter-region transfer charges.

You bring
Rough traffic volumes for the paths you're worried about
You get
A cost estimate per path and a short list of fixes worth checking first
AWS

AWS Storage Cost Calculator

Compare S3 storage classes and find gp2-to-gp3, orphaned-volume, and snapshot-archive savings.

You bring
Rough figures for your S3 data and EBS volumes/snapshots
You get
S3 priced three ways, plus EBS waste broken into three independent fixes
Observability

Observability Cost Calculator

Price Datadog hosts, custom-metric cardinality, and logs alongside AWS CloudWatch's own meters.

You bring
Rough figures for your Datadog hosts, custom metrics, APM, and logs, or your CloudWatch usage
You get
A monthly total broken down by meter, plus a ranked list of the config change behind each saving
Warehouse

Data Warehouse Cost Calculator

Price Snowflake warehouse credits and BigQuery bytes scanned, and see the on-demand-vs-reservation crossover.

You bring
Rough figures for your Snowflake warehouses (size, hours, resumes) or your BigQuery scan volume and storage
You get
A monthly total by meter, the on-demand-vs-Editions crossover, and a ranked list of the config change behind each saving
KubernetesReads your export

Kubernetes Waste Analyzer

Paste kubectl output and see what your own cluster wastes, down to the namespace and workload.

You bring
kubectl get pods -A -o json, plus optionally kubectl top output and a node list
You get
A request roll-up by namespace and workload, and nine findings, dollarized once you add measured usage. Nothing leaves your browser.
AI / LLMReads your export

AI Spend Analyzer

Drop in a Claude or OpenAI usage export and see where the AI bill actually goes.

You bring
An Anthropic Console or OpenAI Usage Dashboard export
You get
A cost breakdown by model, what changed, and nine findings linked to the matching cost-cutting lever. Nothing leaves your browser.
MulticloudReads your export

FOCUS Export Analyzer

Drop in a FOCUS export from AWS, Azure, or Google Cloud and get a conformance check plus a money breakdown.

You bring
A FOCUS-formatted cost and usage export from AWS, Azure, or Google Cloud
You get
A conformance check, a money breakdown by charge category and provider, and seven findings such as unused commitment spend. Nothing leaves your browser.
Planning

Cost Allocation & Tag Coverage Scorer

Score how much of your bill can be pinned to a team, project, or customer.

You bring
A rough sense of your tag coverage, accuracy, and how many teams share the bill
You get
An allocation confidence score, the dollars you can't attribute, and a starter tag schema plus Terraform, AWS Organizations, and IAM artifacts
AWSReads your export

Tag Coverage Analyzer

Drop in two AWS Cost Explorer exports and see the real share of your bill nobody owns.

You bring
An AWS Cost Explorer export of all costs, and the same report with untagged resources only
You get
Coverage by dollars, the trend across periods, which services carry the untagged spend, and a never-tagged-versus-drift split. Nothing leaves your browser.

You're trying to plan ahead

Model what a feature, a customer, or next quarter is going to cost before it happens.

Planning

Savings Calculator

Estimate what rightsizing, commitment coverage, and idle cleanup could save on your current bill.

You bring
A rough monthly cloud spend number
You get
An estimated savings range across the three biggest levers
AI / LLM

LLM Cost Calculator

Model token volume and prompt caching to see what an AI feature costs per request.

You bring
Expected request volume and rough input/output token counts
You get
A cost per request and per month, with caching modeled in
Planning

Cost Per Customer & Unit Economics Calculator

Blend your cloud, AI, and SaaS spend against customers and revenue to see your real margin.

You bring
Total monthly spend, customer count, and MRR
You get
Cost per customer, gross margin, and how it compares to SaaS benchmarks
Planning

Cloud & AI Spend Forecast Calculator

Project your run-rate and the month you'd cross budget from your current spend and growth rate.

You bring
Current monthly spend and an expected growth rate
You get
A 12-month projection and the month you'd cross a budget line
Reference

LLM API Pricing Reference

Every Claude, GPT, and Gemini API list price in one table.

You bring
Nothing. It's a reference table
You get
Input/output cost per million tokens, context window, and tier for every major model
Reference

FOCUS: the FinOps Cost & Usage Standard, Explained

Plain-English definitions of BilledCost, EffectiveCost, ListCost, and ContractedCost, plus a sourced provider-support matrix.

You bring
Nothing. It's a reference page
You get
The four FOCUS cost columns explained with a worked example, a provider-support matrix, and the version history through 1.4

FAQ

Common questions about the free tools

Do I need to sign up to use these tools?

No. Every tool on this page runs in your browser without an account, and using one doesn't put you on a mailing list.

Where does my data go when I use a calculator or drop in a file?

Nowhere but your own browser. This is a static site with no backend to send anything to. Open your browser's Network tab while you use any tool here and you'll see nothing sent out.

Are the results accurate enough to plan a budget around?

Treat them as a starting estimate, not a guarantee. Each tool models a specific scenario from the numbers you give it, and a real bill has edge cases a simplified model won't catch. Use the output as a direction to check, not a final number.

I already have a bill open. Which tool should I use first?

Start with the AWS Bill Analyzer if you have a Cost Explorer CSV, or the AWS Bill Decoder if you just need to know what one line item means.

How often are the numbers in these tools updated?

Each tool lists a last-updated date. Reference tables like the LLM API pricing list get refreshed when a provider changes its rates; the calculators are updated whenever the AWS or vendor pricing they're built on changes.

Can I ask for a tool CostMon doesn't have yet?

Yes. Tell us what you're trying to figure out on the contact page, and if it's a question enough people are asking, we'll build a calculator for it.

See what your stack really costs.

Connect your first providers in minutes and give finance and engineering one number they both trust. Flat pricing, never a percentage of your bill or your savings.

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