AWS access keys are long-lived credentials that never expire on their own — a key created three years ago authenticates exactly as well today as the day it was issued, unless someone actively rotates or deactivates it. That is precisely why credential rotation is a manual discipline rather than something AWS enforces automatically, and why it is easy for a key to silently age well past when it should have been replaced. IAM Access Key Rotation Calculator takes an access key's creation date and tells you its exact age, the date it should be rotated by, and how many days remain (or how many days overdue it already is).
The default rotation interval shown is 90 days, because that figure is widely cited as a security best practice — it appears, for example, in the CIS AWS Foundations Benchmark's guidance on credential rotation. It is not an AWS-enforced limit of any kind. AWS access keys have no built-in expiration and are never force-rotated by the platform; 90 days (or 60, or 180, or whatever your organization's own policy specifies) is purely a self-imposed operational discipline. This tool makes the interval a plain number input rather than hardcoding 90, so you can match whatever rotation cadence your own security policy actually requires.
Enter a key's creation date and the tool reports its age in days, computes the exact date it is due for rotation (creation date plus the interval), and classifies it as fresh (well within the interval), due soon (within 14 days of the interval), or overdue (past the interval) — with the exact days remaining or days overdue shown either way. For checking many keys at once — a realistic need when auditing an account with dozens of IAM users — paste one creation date per line into the batch box and every key is evaluated against the same interval in a single table.
Nothing about your actual AWS account is touched: you supply the creation date(s) yourself (copied from the IAM console's Security Credentials tab or from aws iam list-access-keys output), and every calculation runs locally in your browser against your machine's current date.