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.
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.
Need it as an auditable file?
Ships inside the linked template — formula-driven, unlocked, audit-ready.
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. Treat “excel cast text to number” as a small repeatable workflow rather than a one-off click you hope to remember next time. Use a small test block before the live file, so any surprise in the affected cells shows up while it is still harmless. 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. That turns a calculation you can defend to a CFO or an auditor into a method you can reuse, explain, and defend when the workbook leaves your screen.
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. A practical tip before you scale it up: build it once on a small block of test data, confirm the number against the tool on this page, and only then point it at your real sheet. That one habit catches almost every mistake while it is still cheap to fix, long before a wrong figure reaches a report or a colleague.
In Google Sheets
Everything above works in Google Sheets too. Excel and Sheets share the formula syntax used here; only the surrounding menus are arranged differently. That portability is deliberate — learn it once and it follows you between the two tools and across Windows and Mac. 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, the tool proves it, and the detail above shows why it holds — so the next time a colleague asks, you can answer without reaching for search. The short version of “excel cast text to number”: the answer is at the top of this page, the tool proves it on your own numbers, and the sections above explain why it holds so the next variation does not stump you. Excel rewards people who reference cells instead of typing values and who keep inputs separate from formulas, because that is what makes a result you can audit months later. Build it once, deliberately, with the live tool as a check, and you convert a one-off lookup into a reusable skill — which is the whole point of learning the why and not just the what.
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.
Other ways people ask this
This is also commonly searched as “excel shows decimal number text box everywhere” and “excel shows decimal number text everywhere”. They describe the identical operation, so you are in the right place no matter how you phrased it.
Why do people search for this in so many different ways?
Because the same task has many names. “excel shows decimal number text box everywhere”, “excel shows decimal number text everywhere” all point at the one operation explained on this page, which is why they all lead here.