CSV Header Editor
Rename and edit CSV column headers
Rename the column headers in a CSV file without touching the data. Edit any header name, preview the result, and download the updated file.
This is usually about matching a destination. Import tools map columns by header name, so an export with Email Address will be rejected by a system expecting email — and renaming a wide file by hand in a spreadsheet is tedious and easy to get wrong.
It is also the fix for headers that are technically broken: names with trailing spaces, an invisible byte order mark stuck to the first column, or duplicated names that make a column impossible to address downstream.
Drop your file here or browse from your device
Accepts CSV, TSV, TXT. Maximum input: 10 MiB. Files above this hard limit are rejected before local processing.
How to Convert
- Upload your CSV file or paste CSV data
- Edit the header names to match what you need
- Check the preview to confirm each header sits above the right column
- Download the CSV with the updated headers
Features
- Rename any column header inline
- Preview the updated header row with your data
- Fix headers carrying stray whitespace or invisible characters
- Resolve duplicate header names that break downstream mapping
- Data rows are left untouched — only the header line changes
- Runs entirely in your browser — no upload
Use Cases
- Match the exact header names an import template expects
- Clean up cryptic database column names before sharing a file
- Fix headers rejected by a validation step
- Standardise header names across several files before merging
- Resolve duplicate column names that break a mapping step
Frequently Asked Questions
Does editing headers change my data?
No. Only the header line is rewritten; every data row is left exactly as it was.
Why does my import reject a file that looks correct?
Header names are matched exactly by most import tools. A trailing space, different capitalisation, or an invisible byte order mark on the first header is enough to fail the match even though the file looks fine.
Can I add a header row to a file that has none?
No — this tool edits the headers that exist. A headerless file needs a header row added first, since the first data row would otherwise be consumed as headers.
What about duplicate header names?
Rename them here. Duplicates make a column ambiguous to address, and many tools silently keep only one of them.
Can I reorder or delete columns too?
Not here — use the CSV column reorder tool, which moves and removes columns.
Is my file uploaded?
No. Editing happens in your browser and the contents are not sent to the app server.