Cellwise Fix
AI Excel formula helper: fix or write any formula, checked on your data
Paste your cells and say what you need. You get the formula for your exact sheet, and a real spreadsheet engine runs it on your data before you see it.
Step 1: Your data
DoneOnly want a formula explained? You can skip this step.
My table doesn’t start at A1
Then the formula uses the same cell addresses as your sheet.
Step 2: What do you need?
DoneLooks like you want a new formula ·What does the cell show?Or try an example:Choose the cell for the answer
Leave it empty and we’ll use the first free cell next to your data.
Step 3: Get your answer
DoneStart with step 1 or 2: paste your data, or type what you need.
2 free answers a day, no account needed
AI answers are paused right now. Explaining a formula works fully, and we still look for the cause of a broken one in your cells.
How it works
1. Bring your cells
Copy them from Excel or Google Sheets and paste. Or open a CSV or Excel file, snap a photo of the sheet, or start from a sample.
2. Say what you need
“Totals by region, biggest first.” Or paste the formula that shows #N/A. Or one you inherited and want to understand.
3. Get a checked formula
One big Copy button, the cell to paste it in, a preview of what you’ll see, and a short lesson on why it works.
Why “checked on your data” matters
An AI can write a formula that looks perfect and still fails on a real sheet. The range stops one row short. It sums the wrong column. Or the lookup returns #N/A because three of your IDs have a trailing space you cannot see.
Cellwise Fix runs every formula through the same spreadsheet engine that checks every lesson in the Cellwise course, on the cells you pasted. If the result is not what the answer promised, it asks again with what the engine really got. If the engine cannot run a function, it tells you to test that one in Excel. It never shows a check that did not happen.
Write, fix or explain
Write
Plain English in, the formula for your cells out. Totals by category, lookups, counts between dates, top values, text cleanup.
“Count orders over $500 from the East region”
Fix
Paste a broken formula or the error you see. You get the cause in one line, then the fixed formula, checked on your data.
=VLOOKUP(E2,A2:C7,3,FALSE) shows #N/A
Explain
Paste any formula. See it as a tree of parts, each with what it returns on your data, then step through it inside out, like Excel’s Evaluate Formula.
Free, no limit, runs in your browser.
The errors it explains
Each one has a full guide with the usual causes. Paste the formula above and Cellwise Fix finds which cause it is on your sheet.
“Not working” guides
- VLOOKUP not working: 7 causes and fixes
- COUNTIF not working: causes and fixes
- SUMIFS not working or returning 0: how to fix it
- COUNTIFS not working: why it returns 0 or #VALUE!
- XLOOKUP not working: how to fix #N/A and wrong results
- INDEX MATCH not working: causes and fixes
- IF formula not working in Excel: causes and fixes
- DATEDIF not working in Excel: causes and fixes
- Conditional formatting formula not working: how to fix it
FAQ
Is Cellwise Fix free?
Yes. Explain, step-through and the engine's own checks of your formulas are free with no limit, and they run in your browser. AI answers (writing or fixing a formula) are 2 a day without an account, 5 a day with a free account and 40 a day with Cellwise Plus.
What does “Checked on your data” mean?
The formula was run by the Cellwise spreadsheet engine on the exact cells you pasted, it returned no error, and its result matched what the answer said it would show. If the first answer fails that check, Cellwise asks again once with what the engine really got. You only see the green badge when the check truly passed.
What if it cannot check a formula?
The engine runs about 150 of the most used Excel functions. If a formula uses one it does not run, such as INDIRECT or OFFSET, you see “We couldn’t check this one” and a tip to test it on a copy of your sheet, never a made-up result.
How do I paste my data?
Select the cells in Excel or Google Sheets, copy them (Ctrl+C, or ⌘C on a Mac), then paste them into the box in step 1. Dates become real dates, percentages become numbers, and text keeps every space, because a stray space is often the bug. If your table does not start at A1, open “My table doesn’t start at A1” and type the cell it starts at so the formula uses your real addresses. You can also open a CSV or Excel file.
My Excel uses semicolons. Will the formula work?
Yes. Under the answer, open More and pick Semicolons, and the formula is copied the way Excel shows it in most European languages, with semicolons between arguments and decimal commas. You can paste formulas with semicolons too.
Does it work for Google Sheets?
Most Excel formulas work the same way in Google Sheets. When an answer needs a different function there, it says so. Google Sheets set to a language that writes decimal commas also uses semicolons, so the separator switch helps there too.
Is my data stored?
The engine check runs in your browser. When you ask for an AI answer, the cells you pasted (up to 40 rows and 12 columns) and your question go to Anthropic, our AI provider, to write the answer; we do not keep them. Your recent fixes are saved only in this browser, and a share link carries the sheet inside the link itself.
Which Excel versions do the formulas work in?
When the clearest formula uses functions that Excel 2019 and older do not have, such as XLOOKUP, FILTER, UNIQUE or LET, the answer also gives a version that works there, and the engine checks that it gives the same result.