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Create your Kostrix account: 30 days free on every plan, no card needed

Pick a plan — 30 days free. Your e-mail is verified first. No card needed: the full product is yours for 30 days the moment your account exists. Subscribe when you are ready, during the free days or after, with a payment method - a one-off $1 charge registers the mandate - and the plan's price is charged monthly from the day after the free days end. Launch offer: every plan is 50% off for a limited time - the struck-through figure is the full price, the one beside it is what is charged. Every plan runs every check; they differ only in how many AWS accounts you link.

Your plan — 30 days free, no card needed · Launch offer: 50% off for a limited time

Only so we can reach you about your account; never shown to anyone else.

12–30 characters with an uppercase letter, a lowercase letter, a number and a symbol.

Asked with a code we e-mail you, to verify this address and if you ever reset your password. Capitals, spaces and punctuation don't matter.

Submitting takes you to /aws-cost-optimizer, where the account is created; a six-digit code is e-mailed to you and, once you enter it with your secret answer, you sign in. The next step there is linking your AWS account with read-only access; Kostrix reads the account id from AWS at that moment, so you never type it. Already registered? Log in.

What you will needbefore you start
A work e-mail
It becomes your sign-in name
A password
12-30 characters with upper, lower, a number and a symbol
Read-only credentials
Created from the published CloudFormation stack, on the next page

What the first scan looks at

235 checks across 15 service families, plus Savings Plans and reserved instance coverage. The whole list is published, with the rule identifier each check stamps on its findings.

Already have an account? Log in. Not ready to sign up? Ask us a question first.

From this form to a first scan

Four steps. Only the third touches your AWS account, and it only reads.

  1. 01

    Create the account

    The form on this page: a work e-mail and a password. No AWS account id is asked for - Kostrix reads it from AWS when you link the account.

  2. 02

    Link read-only credentials

    On the next page, in the application. Kostrix calls sts:GetCallerIdentity, records the account AWS reports, and binds your Kostrix account to it from then on.

  3. 03

    The first scan runs

    All 235 checks, every enabled region, a trailing 30-day window. Nothing in your account is changed, because nothing can be.

  4. 04

    Read the uncovered list first

    Before the savings. The billed line items no rule touched are the honest measure of what a first scan did and did not see.

What the first scan looks for

Most AWS cost tools re-draw Cost Explorer in nicer colors and leave you to work out what to do. Kostrix goes the other way: it describes the resources themselves in every enabled region, applies 235 named checks for AWS waste, prices what it finds, and then reconciles the total back against the billed line items so you can see what it did not explain as well as what it did.

That covers unattached EBS volumes and orphaned snapshots, idle and stopped EC2 instances, unassociated Elastic IPs, NAT gateways moving no bytes, load balancers with no healthy targets, RDS and ElastiCache instances nobody connects to, over-provisioned DynamoDB tables, idle Lambda functions, EKS and ECS waste, GPU boxes sitting warm, SageMaker endpoints and Bedrock provisioned throughput nobody calls, plus Graviton and Spot migration candidates and public IPv4 charges. On top of the resource rules it measures savings plans coverage and utilization, reserved instance coverage and utilization, expiry cliffs, sized purchase recommendations.

Every figure is built from a trailing 30-day run rate rather than a partial month scaled up, every percentage carries its unit and its denominator, and a check that could not measure something says so instead of printing a zero. Where AWS will not give a price, the finding is reported without one.

Service families covered

  • Block storage and object storage25
  • EC2 and compute22
  • Networking, CDN and edge27
  • Databases and caches36
  • Analytics, streaming and search26
  • Serverless and integration15
  • Machine learning and AI15
  • Security and compliance22
  • Observability and governance18
  • Media and broadcast7
  • Developer tools and CI/CD8
  • IoT and edge computing4
  • Communications and application services5
  • Commitments3
  • End-user computing2

Every AWS cost check, named and published · Pricing and free trial · The read-only IAM policy