Security API key usage attribution calculator

Calculate unattributed requests inside lookback and unknown key IDs used inside lookback with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use unattributed requests inside lookback and unknown key IDs used inside lookback to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

API key identifiers only: key ID, owner label or none
K1,Alice K2,none K3,Bob
Usage batches: record ID, key ID, date, whole requests; or none
R1,K1,2026-10-19,10 R2,K2,2026-10-20,5 R3,Ghost,2026-10-20,3 R4,K3,2026-10-01,100
Audit date
2026-10-20
Lookback calendar days, including audit day
7
Unattributed requests inside lookback
8
Unknown key IDs used inside lookback
Ghost
Known key IDs with zero lookback requests
K3
Total lookback requests
18
Lookback requests by known key ID
K1: 10; K2: 5; K3: 0
Requests outside lookback, excluded
100
Requests attributed to a supplied known owner (%)
55.555556

Try another scenario

API key identifiers only: key ID, owner label or none
K1,Alice K2,none K3,Bob
Usage batches: record ID, key ID, date, whole requests; or none
R1,K1,2026-10-19,10 R2,K2,2026-10-20,5 R3,Ghost,2026-10-20,3 R4,K3,2026-10-01,100
Audit date
2026-10-20
Lookback calendar days, including audit day
30
Unattributed requests inside lookback
8
Unknown key IDs used inside lookback
Ghost
Known key IDs with zero lookback requests
None
Total lookback requests
118
Lookback requests by known key ID
K1: 10; K2: 5; K3: 100
Requests outside lookback, excluded
0
Requests attributed to a supplied known owner (%)
93.220339
Calculation method

Calculation method

Unattributed requests inside lookback

Sum requests with an unknown key ID or known key owner=none.

Unknown key IDs used inside lookback

Deduplicate unknown key IDs with positive lookback request counts.

Known key IDs with zero lookback requests

Known key IDs whose lookback request sum is zero.

Total lookback requests

Sum requests within [audit−days+1,audit], regardless of ownership.

Lookback requests by known key ID

Sum only matching known key requests.

Requests outside lookback, excluded

Sum requests before or after the selected date window.

Requests attributed to a supplied known owner (%)

(Total−unattributed)/total×100; undefined with no requests.

Symbols and units
a
API key identifiers only: key ID, owner label or none
b
Usage batches: record ID, key ID, date, whole requests; or none
c
Audit date
d
Lookback calendar days, including audit day

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • A supplied usage/ownership audit using nonsecret key identifiers only. Never paste API secrets into these fields. Ownership labels do not verify identity or authorization; no API keys are created, revoked or transmitted to a provider.
Are these inputs private?

These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.

Further reading

NIST SP 800-53: background for inventory, access, audit and contingency controls; worksheet algorithms and rules are explicitly supplied, not NIST compliance tests ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

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