In Excel: select the cells, click the green-triangle warning icon and choose Convert to Number — or convert by formula with =VALUE(A2), the double unary --A2, or A2*1.
On this page7
Select the affected cells — text numbers sit left-aligned and usually carry a green triangle in the corner.
Click the yellow warning icon next to the selection and choose Convert to Number.
For large ranges, select the column and run Data ▸ Text to Columns ▸ Finish — Excel re-parses every cell as a number in one pass.
Alternative bulk trick: type 1 in an empty cell, copy it, select the range, then Paste Special ▸ Multiply.
Or add a helper column with =VALUE(A2) (or --A2), fill down, and paste the results back as values.
Verify: values align right and SUM over the range is no longer 0.
What this does
Numbers stored as text look like numbers but Excel treats them as strings: they align left by default, SUM ignores them, and lookups against real numbers fail. Converting rewrites the stored value as a true number. Changing the cell format to Number is not enough — the format changes how a value displays, not what is stored, so existing text stays text until you re-enter or convert it. Most people learn this as a sequence of clicks and forget it by next week; learning it as a pattern instead is what lets you apply it to the next, slightly different version of the problem without starting from scratch. That is the difference this page is trying to make. The difference between a quick fix and a sheet you can trust is the extra minute you spend validating “excel mass convert to number”. Start on a copy or a tiny sample, keep the affected cells visible, and compare the result with the tool above before you touch the real workbook. When a formula is involved, keep the inputs labelled beside it, reference cells instead of typing values, and apply number formatting only after the result checks out. The point is a data step that keeps your analysis trustworthy, but the practical win is that someone else can open the file and understand what happened without asking you.
A worked example
A2:A4 contain 10, 20 and 30 imported as text — left-aligned, each flagged with a green triangle. =SUM(A2:A4) returns 0. Select A2:A4, click the yellow warning icon, choose Convert to Number: the values jump to the right and SUM now returns 60. Formula alternative: =VALUE(A2) in B2 returns the real number 10. Text numbers arrive constantly from CSV exports, ERP systems and copied web pages; until you convert them, sums, lookups and charts fail silently instead of erroring. If there is any chance you will reuse this, drop it into a small template tab right now: a labelled input area on the left and the formula beside it, checked once against the tool above. Next time the same question comes up, the answer is a single paste away instead of a rebuild from memory.
In Google Sheets
Google Sheets handles this almost identically to Excel. The formula syntax above is the same, and the menu lives under a slightly different label rather than a ribbon tab. Use the platform toggle at the top of the page to switch every keyboard shortcut between Windows and Mac, and expect at most cosmetic differences in naming. The aim was to get you unstuck fast and leave you a little more capable than a copy-paste would. The answer is at the top and the detail above shows why it holds — so the next time a colleague asks, you can answer without reaching for search. Treat “excel mass convert to number” as a small building block rather than a chore. Once the inputs sit in their own cells and the formula reads from them, the same setup answers a dozen related questions with a tweak, and Excel keeps every dependent figure current as the data changes. The tool above is there so you can rehearse and verify before committing anything to a real workbook; the steps and worked example are there so the logic sticks. Get it right once and it stops costing you time — it starts saving it, every time the question comes back around.
Common mistakes
- Formatting the cells as Number and expecting existing text to convert — the stored value does not change until you re-enter or convert it.
- Wondering why
SUMreturns 0:SUMsilently skips text, so a whole column of text numbers sums to nothing. - Importing a US-format CSV on a comma-decimal system: 1.5 arrives as text or gets misread as a date, and VALUE follows your regional decimal separator.
- Ignoring invisible characters — non-breaking spaces and currency symbols from web copies block conversion; clean with
TRIMandSUBSTITUTEfirst. - Looking for the green triangle in Google Sheets — it does not exist there; Sheets usually auto-coerces text numbers in math, and when it does not, use VALUE or Format ▸ Number.
Frequently asked questions
Why does SUM return 0 over my numbers?
They are stored as text. SUM ignores text values entirely. Convert them with the warning icon, Text to Columns, or =VALUE().
What does the green triangle mean?
It is Excel's error check flagging a number stored as text. Click the cell, then the yellow icon, then Convert to Number.
Does this work the same in Google Sheets?
Sheets has no green triangle and usually auto-coerces text numbers in calculations. When it does not, use =VALUE(A2) or Format ▸ Number ▸ Number.