Add sequential row numbers as a new column in your CSV — useful for tracking, referencing, and joining datasets.
Free for files up to 5 MB and 10,000 rows. Files are processed in your
browser — nothing is uploaded to a server. No account required.
About Row Numbering
Add a sequential number column to a CSV. You set the header name, the number to start from, and whether the column goes at the front or the back of the file.
Two situations bring people here. First, you are about to sort or filter a file and want the original order recorded so you can restore it later. Second, you need a stable reference for a conversation, such as telling a support engineer that the broken record is row 4,812 of the export.
Starting from a number other than 1 helps when you are appending a batch to an existing dataset and want the numbering to carry on where the last file finished.
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