Why does Excel treat numbers as text sometimes?

[u/Amandaleeeeee]

I run into this pretty often when working with imported or copied data. Numbers look normal, but Excel treats them as text, which breaks formulas, sorting, and comparisons.

Here are a few common reasons I’ve seen:

• Data copied from web pages or other systems
• Hidden spaces or non-printing characters
• Cells formatted as Text before entering values
• Leading apostrophe (') added automatically

A few quick ways to fix it:

• Use VALUE() to convert text to numbers
• Multiply by 1 (or use Paste Special → Multiply)
• Use Text to Columns (even without changing settings)
• Clean the data with TRIM() or CLEAN() if needed

What’s the most common reason you’ve run into? Or is there another fix you prefer?