Numbers date formatting question

The difference is in the content of the cell. For your first image, the cell contains what Numbers recognizes as a valid date. For your second image, Numbers only sees the cell content as text. Look at the bottom left of the window to see what type of data is in the cell.

For those that are texts you'll have to find a way to convert them, probably manually or by extracting the parts with various functions (TEXTBEFORE, TEXTBETWEEN, TEXTAFTER) and recombining them with DATE. The strategy depends on what the false dates look like and how many you have.

Bomiboll wrote:

I do not understand what is the point with this.

Could you explain a little bit more what is confusing about this for you? It's possible you are overthinking the problem.

If Numbers recognizes a value in a cell as date-time then it tells you by showing the data and time. Those values will sort correctly by date and can also be used for date math (e.g. calculate the number of days between dates by subtracting one from another, etc). If it doesn't recognize the value in a cell as date-time then it often treats it as text, which it will sort differently.

Values recognized as date-time will be right-aligned by default. Text is left-aligned by default.

SG

Left-aligned by default? Or after setting the alignment to left?

That Actual at the lower left indicates Numbers recognizes the value as a date rather than as Text. By default it likely was right-aligned, and subsequently the alignment was changed.

SG

Bomiboll wrote:

Is there a link to a guide on this issue ?

It's hard to know what you mean by "this issue."

You can find the Number User Guide at Help > Numbers Help in your menu or here:

Numbers User Guide for Mac - Apple Support

Check the Table of Contents there. Perhaps the answer to your question is here?

Format dates, currency, and more in Numbers on Mac - Apple Support

SG

Is it still confusing to you now that you have read the explanations here and seen the MacMost video?

Lots of things can be confusing when first learning to use a powerful tool like Numbers, but the confusion should diminish with time.

SG

Not sure exactly what your point is here. Spreadsheet apps are powerful and complicated tools, and can confusing, especially if one doesn't study how to use them properly.

Are you still confused and need help? Or instead are you saying you think you have a better way?

If the latter, you could try communicating with Apple via Numbers > Provide Numbers Feedback in your menu..

SG