Free tool
Workbook X-ray: audit any Excel file in seconds
Drop in a workbook and get a ranked list of the formula risks inside it, with cell addresses. It runs entirely in your browser, so the file never leaves your computer.
Drop your Excel file here
.xlsx or .xlsm, up to 50 MB
Runs entirely in your browser. Your file is never uploaded, stored or seen by me. It works offline once this page has loaded.
How it works
The checks I run first on every workbook, automated
1. Reads the structure
An .xlsx file is a zip of XML. The X-ray unzips it in your browser and reads every formula, error value and sheet setting. It never reads your text or headings.
2. Compares formulas
Each formula is converted to a relative pattern, so a formula that differs from the identical ones above and below it stands out, along with values typed over a formula column.
3. Ranks the risks
Findings are weighted by how likely they are to produce a wrong number, and each comes with the cells to check and how I'd fix it.
Want to check by hand as well? Follow the 10-minute spreadsheet audit checklist, or see the spreadsheet audit and repair service.
Questions
Is my file uploaded anywhere?
No. The X-ray reads the file inside your browser with JavaScript. Nothing is sent to a server, and the page works offline once it has loaded. If you choose to send me your score, only the counts are shared, never the contents of the file.
What does the X-ray check?
It looks for broken references (#REF!), cells showing errors, links to other workbooks, numbers typed over a column of formulas, formulas that break the pattern of their neighbours, numbers typed inside formulas, approximate-match lookups, volatile functions like INDIRECT and OFFSET, whole-column references, very long or deeply nested formulas, hidden sheets, merged cells and macros.
What does the score mean?
It starts at 100 and loses points for each kind of risk found, weighted by how likely it is to produce a wrong number. 80 or more is low risk, 55 to 79 is moderate, and below 55 means some totals are probably wrong today. It's a first pass to decide where to look, not a pass/fail certificate.
Does it fix the file?
No. It tells you what to fix and where. If you'd like it fixed, send me the score and I'll reply with a fixed price, or start with the Scoping Sprint for a written diagnosis and proposal.
Why doesn't it accept .xls or .xlsb files?
Those are older binary formats. Open the file in Excel, choose File > Save As > Excel Workbook (.xlsx), and drop the new copy here. Password-protected files need the password removed first.
How is this different from Excel's own Inquire or Error Checking?
Excel's tools work one cell or one sheet at a time and need you to know where to look. The X-ray scans every sheet at once, ranks the risks, and gives you a list of cell addresses to work through. It's also useful when you don't have the Inquire add-in, which only comes with some Microsoft 365 plans.
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