Add Row Numbers to Excel Files Online
Add a row number index column to Excel files directly in your browser. Set the column name and starting number — no upload required.
How to add Row Numbers to Excel files
- Drop your file onto the upload area. The row count is shown and the first 200 rows are previewed.
- Type a name for the new column. It defaults to row_number.
- Set Start at to the first number you want. It defaults to 1, and 0 or a negative number also works.
- Click Add Row Numbers. The new column appears as the first column in the preview.
- Click Download to save the numbered file in the same format you uploaded.
Your file is processed locally in your browser and is never uploaded. The free limit is 50 MB per file; larger files work if your device has the memory for them.
Worked example
A research team has a batch of survey responses and a second batch already numbered up to 100. They want the new batch to carry on from 101 so the two can be combined later.
Input (Excel)
Excel workbook, first sheet (Sheet1)
| respondent | country | score | completed |
|---|---|---|---|
| r_8f2a | Ireland | 7 | true |
| r_03cd | Portugal | 9 | true |
| r_b771 | Ireland | NULL | false |
| r_5e10 | Canada | 6 | true |
Settings
- Column name: response_no
- Start at: 101
Result
| response_no | respondent | country | score | completed |
|---|---|---|---|---|
| 101 | r_8f2a | Ireland | 7 | true |
| 102 | r_03cd | Portugal | 9 | true |
| 103 | r_b771 | Ireland | NULL | false |
| 104 | r_5e10 | Canada | 6 | true |
A new integer column called response_no is placed in front of the existing columns and counts up by one per row from 101. Numbers follow the order of the rows in the file. The other columns are unchanged, including the missing score for r_b771.
Working with Excel files
Only the first sheet is numbered. The number counts data rows below the header, so row_number 1 sits on spreadsheet row 2. If you want the values to match Excel's own row labels, set Start at to 2. Blank rows inside the sheet's used range are rows too and each gets a number.
The output is a new workbook with one sheet, Sheet1, and the number column in column A. Unlike Excel's =ROW() formula, the numbers are fixed values. They will not change if you later sort, filter or delete rows in Excel, which is usually the point: you can always sort back to the original order. Formatting and formulas from the source sheet are not kept. Hidden rows are numbered as well, because they are read like any other row. The row count shown after loading tells you how many numbers will be assigned.
Frequently Asked Questions
How is this different from filling a column with =ROW()-1 in Excel?
The numbers are written as plain values, not formulas. They stay attached to each record after sorting or filtering, where a ROW() formula would recalculate.
Can I number a sheet other than the first one?
Not directly. The tool reads the first sheet. Extract the sheet you need into its own file first, then add row numbers.
Can I start numbering at 0?
Yes. Set Start at to 0 for zero-based indexes. Any whole number works, including negatives. An empty box or a value that is not a number uses the default of 1, and decimals are cut to a whole number.
In what order are rows numbered?
In the order they appear in the file. The tool does not sort. Sort the file first if you want numbers to follow a date or ID column.
What if I leave the column name blank?
The column is named row_number. Choose a name that is not already used by a column in your file.
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