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CSV Column Renamer

System ideaMissing a tool?

Rename CSV header columns with a simple old=new mapping

Paste CSV data and a list of old=new column name pairs, one per line, to rename header columns while leaving every data row untouched. Runs entirely in your browser.

Renamed 2 column(s) in your browser.

Renamed CSV
identifier,full_name,team
1,Ada Lovelace,Blue
2,Grace Hopper,Green

Everything on this page is processed in your browser. Nothing is uploaded.

What this tool does

Renaming a handful of CSV columns by hand is easy to get wrong once quoted fields are involved, since a text editor's find-and-replace doesn't know the difference between a header cell and a value that happens to match it. This tool parses the CSV properly, applies each old=new pair from the mapping only to the header row, leaves columns not mentioned in the mapping unchanged, and reports any mapping entry whose old name isn't actually present in the header.

How to use it

  1. Paste CSV data, or load the example.
  2. Choose the delimiter, then list old=new column names, one per line.
  3. Copy the renamed CSV, checking for any names not found in the header.

Privacy

This tool runs entirely in your browser. Your input is never uploaded, stored or shared — closing the tab removes it.

Frequently asked questions

Is my data uploaded anywhere?
No. Parsing and renaming happen in JavaScript running in the page, so nothing you paste ever leaves your device.
What happens to columns I don't list?
They keep their original name and position; only the columns named on the left side of a mapping line are renamed.
What if I misspell a column name in the mapping?
That mapping entry is reported back as not found in the header, so you can fix the spelling and try again instead of it being silently ignored.

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