Add Row Numbers to TSV Files Online
Add a row number index column to TSV files directly in your browser. Set the column name and starting number — no upload required.
How to add Row Numbers to TSV 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 (TSV)
respondent country score completed
r_8f2a Ireland 7 true
r_03cd Portugal 9 true
r_b771 Ireland false
r_5e10 Canada 6 trueSettings
- 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.
Frequently Asked Questions
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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