Audit Spreadsheet

Use this skill when the user asks to audit a workbook, check formulas, find spreadsheet errors, QA a financial model, debug why a model does not balance, or sanity-check Excel output.

Step 1: Determine Scope

If the user already gave a scope, use it. Otherwise ask which scope to audit:

• selection: just the currently selected range
• sheet: the current active sheet only
• model: the whole workbook, including financial-model integrity checks

Use model scope for DCF, LBO, three-statement, merger, comps, or integrated financial models before sending to a client, controller, or investment committee.

Step 2: Formula-Level Checks

Run these for every scope:

Check	What to look for
Formula errors	#REF!, #VALUE!, #N/A, #DIV/0!, #NAME?
Hardcodes inside formulas	Constants embedded in formulas that should be inputs
Inconsistent formulas	A formula that breaks the pattern of neighboring rows or columns
Off-by-one ranges	SUM or AVERAGE ranges that miss first or last rows
Pasted-over formulas	Cells that should contain formulas but contain hardcoded values
Circular references	Intentional or accidental loops
Broken cross-sheet links	References to moved or deleted cells
Unit and scale mismatches	Thousands mixed with millions, or percent values stored inconsistently
Hidden rows or tabs	Overrides or stale calculations hidden from normal review

Step 3: Model-Integrity Checks

For model scope, identify the model type and run the relevant checks.

Structural review:

• Inputs, calculations, and outputs are separated.
• Color conventions are used consistently.
• Tabs flow in a logical order.
• Date headers and units are consistent.

Balance sheet:

• Total assets equal total liabilities plus equity in every period.
• Retained earnings roll forward from prior retained earnings plus net income less dividends.
• Goodwill and intangibles flow from acquisition assumptions when relevant.

Cash flow:

• Cash flow ending cash ties to balance-sheet cash.
• CFO plus CFI plus CFF equals change in cash.
• D&A, capex, and working-capital changes tie to supporting schedules and signs.

Income statement:

• Revenue ties to segment or product detail.
• Tax expense is reasonable against pre-tax income.
• Share count ties to dilution schedules when relevant.

Model-specific checks:

• DCF: discount timing, terminal value discounting, WACC basis, unlevered FCF, tax shield treatment.
• LBO: debt paydown, PIK accrual, rollover treatment, exit EBITDA basis, fees and expenses.
• Merger: accretion/dilution share count, synergy phase-in, purchase price allocation, sources and uses.
• Three-statement: working-capital signs, depreciation to PP&E, debt maturity schedule, dividend logic.

Step 4: Report

Return a findings table:

#	Sheet	Cell/Range	Severity	Category	Issue	Suggested Fix

Severity:

• Critical: wrong output, broken formula, balance sheet does not balance, cash does not tie.
• Warning: risky hardcodes, inconsistent formulas, edge-case failures.
• Info: style or best-practice issues.

For model scope, prepend:

Model type: <type> - Overall: <Clean / Minor Issues / Major Issues> - <N> critical, <N> warnings, <N> info

Do not change the workbook without asking. Report first, then fix only on request.