Step by step
Apply the method to one real task.
Extract source values and units
Copy every input value from the task packet and label its unit, sign, and meaning. Do not silently repair or infer a missing value.
- Checkpoint
- Every number in the calculation maps to a stated source value or a clearly named derived value.
Write the operation order
Express the calculation as explicit operations before recomputing it. Confirm which subtotal a rate or contingency applies to.
- Checkpoint
- A second reviewer can reproduce the intended sequence without reading the model prose.
Recompute intermediate values
Calculate each subtotal independently and retain sufficient precision through the intermediate steps. Record, rather than hide, any rounding rule.
- Checkpoint
- The first differing intermediate value identifies where an error begins.
Reconcile the final result
Use an inverse, alternate grouping, or sum check where possible. Confirm units, sign, magnitude, and whether the final label matches the number.
- Checkpoint
- The final amount agrees with the independently reconstructed path and a reasonableness check.
Separate arithmetic from assumptions
State whether the arithmetic is correct independently from whether the inputs, rate, business rule, or forecast assumption is appropriate.
- Checkpoint
- The acceptance statement says exactly what was verified and what was not.
Decision rules
Make the boundary explicit.
- Reject the calculation if a required source value, unit, or operation cannot be traced.
- Do not round intermediate monetary values unless the task or governing rule requires it.
- A correct final number with an irreproducible path is not fully auditable.
- Arithmetic verification does not validate the business or domain assumptions behind the inputs.
Reusable artifact
Calculation audit worksheet
Copy the template into your notes, or download a Markdown file and keep it with the task evidence.
Preview the template
# AI Calculation Audit
## Claim to verify
- Claimed result:
- Unit:
- Intended decision or use:
## Source values
| Label | Value | Unit | Source |
| --- | ---: | --- | --- |
| | | | |
## Reconstructed calculation
1. Operation:
- Intermediate value:
2. Operation:
- Intermediate value:
## Checks
- Rounding rule:
- Alternate or inverse check:
- Unit and sign check:
- Magnitude check:
## Decision boundary
- Arithmetic: Correct / Incorrect / Unresolved
- First mismatch:
- Assumptions not verified:
- Human reviewer:
Linked evidence
Inspect where this method was applied.
- Budget math Reviewed Case
A deterministic example with three captured calculations and an explicit arithmetic proof.