Want proof before you pay?

Send one representative formula with fictional or redacted sample inputs and the result you expected. I will return one private screenshot showing the likely issue category and one boundary-test result at no charge. The free proof does not include a corrected reusable formula, edited workbook or source file.

Request a scope quote online Email the free one-formula proof

Remove names, account numbers and other sensitive data. Full diagnosis and reusable corrections begin only after the paid review is confirmed.

One formula — CAD 9

One formula and its surrounding context
Likely cause and corrected-formula recommendation
Short boundary-test checklist
One clarification round
Diagnosis within 24 hours after complete material arrives

Workbook mini review — CAD 19

One .xlsx workbook
Up to three formula, duplicate-data or formatting issues
Written cause and recommended corrections
Checks for first, middle, last and newly added rows
One clarification round
Diagnosis within 24 hours after complete files arrive

What a useful diagnosis looks like

Fictional example. It demonstrates the review method, not past client work.

Observed formula	Risk	Recommended pattern	Test
`=IF(C2="Paid",D2*E2,0)`	Text variants such as “paid ” silently return zero.	`=IF(UPPER(TRIM(C2))="PAID",D2*E2,0)`	Test Paid, paid + trailing space, blank and a new row.
`=VLOOKUP(A2,Rates!A:B,2,FALSE)`	Missing IDs show an error without explaining the missing key.	`=IFNA(XLOOKUP(A2,Rates!A:A,Rates!B:B),"Missing rate")`	Test valid, missing and duplicate IDs.

What a careful cleanup review looks like

Fictional examples. Ambiguous source data is flagged for confirmation rather than silently guessed. Download the sample change log as CSV.

Sample issue	Review response	Acceptance check
`Acme ltd` appears beside `ACME LTD`	Normalize case and whitespace only after confirming both rows represent the same customer.	One approved record remains; no unrelated row is removed.
`01/02/26` has no stated date locale	Flag the value as ambiguous instead of assuming January 2 or February 1.	Source locale is confirmed and the resulting Excel date serial is verified.
`$1,200` is stored as text	Confirm currency and separators, then convert the underlying value rather than changing display formatting alone.	`ISNUMBER` returns TRUE and the displayed amount remains correct.

Prefer a self-guided workflow?

The CAD 5 Excel Formula Debug Workbook is an instant download with six diagnostic checks and twelve boundary-test rows. Choose the review service above when you want a written second opinion on the formula itself.

Before buying a review

Email maxiaofeng@foxmail.com if the workbook contains macros, Power Query, external connections or more than three issues. Direct Checkout is intended for Canada/US customers and international business buyers; EU/UK consumers should email before paying.