= Write My Formula

Excel formula fixer

Fix a broken Excel formula without guessing at syntax.

Paste the formula that is failing and get a corrected version with notes about common errors and safer fallbacks.

Request

Formula request

2 guest tries left
Mode
Spreadsheet
Upgrade $9

Purpose-built inputs

A focused workflow for everyday spreadsheet work.

Structured formula builder

Task, table context, target range, and function hint keep the request specific.

Write / Explain / Fix modes

Generate a new formula, translate a pasted one, or diagnose common syntax issues.

Excel and Sheets toggle

Compatibility notes call out modern functions and platform-specific behavior.

Formula-bar output

The result is formatted for scanning and placed next to a copy button.

Common formulas

Pick the formula you came for.

Percentage formulas

Build percent of total, percent change, discount, markup, tax, tip, and completion-rate formulas.

Date formulas

Create due dates, workday counts, month-end dates, date differences, and overdue checks.

FILTER formulas

Return matching rows for status, region, date, text, and threshold conditions.

Text formulas

Split, extract, join, trim, clean, and replace text from messy imported cells.

Data validation formulas

Block bad IDs, duplicate values, missing fields, and invalid entries with custom TRUE/FALSE rules.

XLOOKUP formulas

Return matching values with separate lookup and return ranges.

INDEX MATCH formulas

Build flexible lookup formulas for left lookups, two-way lookups, and older Excel files.

SUMIFS formulas

Total rows that match status, date, category, customer, or region rules.

Use case

Excel formula fixer for spreadsheet work.

Turn a formula that errors or behaves strangely into a safer Excel formula.

What this page gives you

  • A safer draft version of the formula that is failing.
  • A short explanation of likely syntax, range, or fallback problems.
  • Checks that help you test the fixed formula against known rows.

When to use it

Use this page when a formula returns an error, breaks after being filled down, or needs a clearer fallback for missing matches.

Do not replace a working report formula across a whole workbook before testing. Fix one row first, then compare the result against the original data.

Worked example

A lookup formula can be made safer by adding a not-found fallback.

=XLOOKUP(A2,Customers!A:A,Customers!C:C,"Not found")

The formula searches customer IDs in column A of the Customers sheet and returns column C, with a readable fallback when no match exists.

Check before you paste

  • Make sure the corrected range sizes line up.
  • Keep backup copies of formulas before replacing a working report.
  • Test the fixed formula on both a matching row and a missing-match row.

Upgrade when the work piles up

Keep going when the sheet gets complicated.

Try twice as a guest. Free accounts get 3 runs per week plus a monthly product email. Upgrade when formula work becomes a recurring part of the week.

Founding access

$9

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