I asked here last week as to why the box that allowed you change from numbers being text to numbers.

Question

I asked here last week as to why the box that allowed you change from numbers being text to numbers.

William Auld 160

Its annoying having any numbers on your spreadsheet little black triangles in the left/hand top corner. I got a reply:, "rather than the table heading, and press Alt+Shift+F10 to open its error-checking menu. Choose Convert to Number if that is the reported issue." This didn't work, so I found that if you hoover over the black triangle a box appears stating "Fix this error" or "Ignore error" if you hit the "Ignore error" and providing you have highlighted all the affected cells the error clears. The triangles may reappear in which case go to format cells and under custom change to 0:00 to 0.

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Answer 1

Kai-H 27,725 Microsoft External Staff Moderator

Hi, William Auld

The triangle means Excel sees the entry as text, even though it looks like a number. Changing the cell format alone does not change the underlying value, and 0:00 is a time format, so it should only be used for times.

Here are some suggestions you can try:

Select the affected column, then go to Data > Text to Columns. Choose Delimited, select Next twice without selecting a delimiter, choose General, and select Finish. This forces Excel to recognize the existing entries again without splitting the column. The Text to Columns wizard is available in desktop Excel.

Enter 1 in an empty cell and copy it. Select the affected numbers, then choose Home > Paste > Paste Special > Multiply > OK. Multiplying by 1 changes text-based numeric entries into real numbers without changing their values. This is an alternative conversion method documented for text-formatted numbers.

If the numbers came from a website or CSV file, also check whether commas and decimal points match your Windows regional settings, since mismatched separators can cause Excel to import numbers as text.

Thank you for your patience in reading, I hope this information has been helpful to you.

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Kai-H 27,725 Reputation points Microsoft External Staff Moderator

2026-09-16T09:16:21.5566667+00:00

Hi, William Auld

It has been a while and I am writing to see how things are going with this issue.

Have you had a chance to check the replies provided?

Any update would be appreciated.
William Auld 160 Reputation points

2026-09-16T18:13:33.52+00:00

It might have been a good idea to let us all know that there have been a few changes made to Excel. Something along the lines like there will be black triangles appearing in your cells from now on. As far as my worksheets are concerned I am working my way through them and have nearly completed the task of removing them where found. I use the method as suggested by Copilot, that is hoover over any cells and when the "Ignore error" appears-click it. To date this method appears to work in that I have w/s with no black triangles. We at the coalface appreciate the extra work involved in cleaning up Excel's mistakes.
Kai-H 27,725 Reputation points Microsoft External Staff Moderator

2026-09-17T06:42:42.2966667+00:00

Hi, William Auld

I understand the frustration, especially when you have many existing worksheets to clean up.

For clarity, these corner triangles are part of Excel’s background error checking and are not necessarily evidence of a recent change. They indicate that Excel has detected a possible issue, such as a number stored as text or a formula that differs from nearby formulas. The data itself may still be correct.

Using Ignore Error is appropriate when you have checked the cells and intentionally want the values kept as they are. You can also apply it to several cells at once by selecting the entire affected range, selecting the warning button, and choosing Ignore Error. This removes the indicator for that range without changing the values.

One caution: ignoring the warning does not correct the underlying data type. If those entries are later used in calculations, sorting, or totals, it is worth checking that Excel recognizes them correctly.

Thank you for sharing what worked. Your feedback about clearer communication and the amount of cleanup involved is understandable.

Answer 2

The black triangles are Excel error indicators showing that numbers are stored as text. To remove them for the selected cells without converting the values, select the cells, select the warning box, and choose Ignore Error. If the triangles return, that usually means new or existing values are still being treated as text.

If the values should be real numbers, use Convert to Number instead:

Select the affected cell or range.
Select the error indicator or press Alt+Shift+F10.
Choose Convert to Number.

If Convert to Number is not available or does not work, use a formula-based conversion:

Insert a new column next to the text values.
Enter =VALUE(cell) using the first affected cell reference.
Fill the formula down.
Copy the results.
Use Home > Paste > Paste Special > Values to replace the original text values.

If the goal is only to hide the triangles, error checking for this condition can be turned off:

Select File > Options.
Select Formulas.
Under Error checking rules, clear Numbers formatted as text or preceded by an apostrophe.
Select OK.

If the entries are intended to stay as text, format the cells as Text before entering them. Excel notes that left-aligned numbers usually indicate they are not formatted as numbers.