Excel shows #### instead of the value — what it means and what is really in the cell
A run of number signs is not a value. It is Excel declining to show a number or a date that does not fit the width of the column, or a date it has worked out to be before the year 1900. Widen the column and the number appears. If the file came from a CSV, the file still holds the exact text it was given, and opening it here shows that text without Excel deciding what it is.
The two things #### means
The common one is width: a number or a date is wider than the column, and Excel will not show half of a number the way it shows half of a word, so it fills the cell with signs instead. Double-click the boundary at the right of the column heading and the value appears. Text is never shown this way, which is the first clue that Excel has read the cell as a number or a date.
The other one is a negative date or time. Subtract a later date from an earlier one, or let a cell become a number below zero while formatted as a date, and Excel shows signs at any width, because it has no way to draw a day before its calendar starts. The underlying number is there; the format is what fails.
See what the file actually says
When the signs appeared the moment a CSV was opened, the question is not what Excel is showing but what Excel decided the value was. Open the same file in the editor here and every cell is shown as the text in the file — a reference number of sixteen digits stays sixteen digits, a date stays the way it was written — because nothing is turned into a number on the way in.
That is also the check for whether anything has been lost: if the editor shows the value you expect, Excel only hid it; if the file itself now holds 1.23E+15 or a rounded number, it was saved from Excel after the value changed, and the original export is where the data is.
Keep Excel from changing it next time
Long identifiers, account numbers and codes with leading zeros are safest as text cells, which Excel shows in full at any width and never rounds. The CSV to Excel converter here writes every value as a text cell, so a workbook made from it opens with the values as written — and stays that way when it is saved again.
The Excel check page on this site shows, for any column you paste, exactly what Excel would do to each value before you open a file: which ones become dates, which lose their zeros, which are rounded past fifteen digits.
Questions
- Is the value gone when Excel shows ####?
- No. The cell still holds the number or date; the signs are only the display. Widen the column, or check the value in the formula bar with the cell selected.
- Why does widening the column not help?
- Then the cell holds a negative date or time, which Excel cannot draw at any width. Look at the formula bar: a negative number formatted as a date is the usual cause, often from subtracting two dates the wrong way round.
- Why is only one column showing signs after opening a CSV?
- Because that column holds values Excel read as numbers or dates too wide for the default column width — long ids, timestamps, large amounts. The other columns were read as text, which Excel clips rather than hides.
- Can I stop Excel from turning my ids into numbers at all?
- Yes, by giving it a workbook where they are text cells. The CSV to Excel converter here writes every value as text, so the ids are shown in full and are never rounded or turned into dates.
- How do I see the real values without Excel?
- Open the CSV in the editor here. It shows every cell as the exact text in the file and downloads it the same way, so nothing is reinterpreted in either direction.
- Is my file uploaded anywhere?
- No. The ##### was only ever a display problem, and seeing the real values involves nothing leaving your device — the editor reads the text in your file on your machine and shows it as written.