CSV Column Editor
Extract, reorder and merge CSV columns. Combine "First name" and "Last name" into a single "Full name" column, or reshape a contact list before importing it elsewhere. Everything runs in your browser — your data is never sent anywhere.
Your data is processed entirely in your browser and is never sent anywhere.
Load a CSV to see the column options and result here.
How to use
- Paste your CSV and click "Load" to see the list of columns.
- Check the columns you want in the output, and use the up/down buttons to set their order. To combine columns, pick two or more under "Merge columns", set a separator and a new column name, then click "Add merge".
- Click "Convert" to see the result, then "Copy result" to copy it to your clipboard.
How it works
How column operations work
Extract and reorder
After loading a CSV, check the columns you want in the output. Checked columns are output in the order shown, top to bottom — use the up/down buttons to change that order. Selecting every column lets you use the tool purely to reorder columns.
Merge
Join two or more columns with a chosen separator to create a new column. For example, merging "first_name" and "last_name" with a space produces a "full_name" column. The original source columns aren't removed — when choosing which columns to output, you can include just the merged column, keep the originals too, or any combination.
You can define more than one merge. A column created by an earlier merge can be used as a source for a later one (e.g. first_name + last_name → full_name, then full_name + zip → full_name_and_zip).
Processing order
- Load the CSV
- Apply every defined merge, in the order they were added
- Output the selected columns, in the order chosen
About CSV parsing
Fields wrapped in quotes can safely contain commas or line breaks. If rows don't all have the same number of columns, you'll get an error.
Limits
The tool processes up to 5,000,000 characters at a time, and up to 20 merges can be defined. Exceeding either limit shows an error instead of converting.
FAQ
Is my CSV sent anywhere?
No. Column operations and conversion happen entirely in your browser — nothing is transmitted to a server.
Can I combine "first_name" and "last_name" into one "full_name" column?
Yes. Under "Merge columns", select first_name and last_name, set a separator (like a single space) and a new column name such as full_name, then click "Add merge". Select full_name under "Columns to output" if you only want the merged column in the result.
Can I reorder columns by dragging them?
Drag-and-drop isn't supported. Use the up/down buttons instead — this keeps the tool fully usable with a keyboard.
Do the original columns disappear after I merge them?
No, merging only adds a new column — it doesn't remove the source columns. If you don't want the originals in your output, just leave their checkboxes unchecked under "Columns to output".
How many merges can I define, and how large a CSV can I process?
Up to 20 merges, and up to 5,000,000 characters of CSV input. Going over either limit shows an error instead of converting.
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