Insert a CSV Column
Quickly insert one or more new columns anywhere in a CSV file. Runs entirely in your browser, so your data never leaves your device.
0 chars · 0 lines
Output
The result appears here as you type.
How to use Insert a CSV Column
- 1. Paste the CSV. Enter the rows in the input pane. Unlike simple prepend or append, this tool can place the new column between any two existing columns without disturbing their contents.
- 2. Pick the position. 'Insert at position' takes a 1-based column number; entering 2 makes the new column the second one, pushing the old second column and everything after it one place to the right.
- 3. Name and fill the column. Column name labels the header cell and 'Fill value for data rows' seeds every data cell. Keep First row is header checked so the name lands in the header instead of the first record.
- 4. Copy the result. Copy the widened CSV from the output pane and verify one row visually. If the column landed one position off, adjust the number and the output regenerates immediately.
When to use Insert a CSV Column
Insert a CSV Column places a new column at an exact position inside a file. Import mappings and fixed-order templates frequently care about column order, not just column presence, so a field added at the end is not good enough. This tool slots the column precisely where the schema says it belongs.
- Matching a strict import layout. A payroll upload defines column 3 as middle_name and your HR export skips it. Insert an empty middle_name column at position 3 so every later field maps to the right slot.
- Keeping related fields adjacent. You are adding a currency column and want it right after amount, not stranded at the end of forty columns. Positional insert keeps the pair together for anyone reading the file.
- Restoring a column a script dropped. A cleanup script accidentally removed the second column from an archive file. Re-insert it at position 2 with a placeholder fill so old and new files share one schema again.
Examples
Insert a column as the second column
Input
name,age Ada,36
Output
name,middle,age Ada,,36
About the Insert a CSV Column tool
Insert a CSV Column runs as plain JavaScript in your browser tab, with no server behind it. Quickly insert one or more new columns anywhere in a CSV file. Whatever you put in stays on your device from start to finish.
The tool is part of EditSafely's CSV Tools section, 133 single-purpose utilities built around the same idea: open the page, get the result, keep your data to yourself.
You can shape the output with 4 settings, including Insert at position, Column name, Fill value for data rows and First row is header, and the result refreshes the moment you change one. A worked example further down the page shows exactly what the tool produces for a real input.
That local-first design has practical benefits beyond privacy. The tool keeps working on a flaky connection once the page has loaded, results are instant because nothing round-trips to a server, and it is safe to use with confidential material.
Frequently asked questions
Does Insert a CSV Column cost anything?
Yes, it is completely free. All 2,658 tools on EditSafely work without an account, a subscription or usage limits.
Is it safe to paste sensitive or confidential data?
No data leaves your device. The whole tool is JavaScript that runs inside your browser tab, so there is no upload, no server-side processing and no log of what you did. If you disconnect from the internet after the page loads, it keeps working.
How much text can I process at once?
There is no fixed limit. Because the work happens on your own device rather than on a shared server, the practical ceiling is your machine's memory, which comfortably handles inputs far larger than typical online tools allow.
Do I need to sign up or install anything?
Nothing to install and no account needed. Open the page in any up-to-date browser, including on a phone or tablet, and the tool is ready.
How do I use the result?
The output panel has a one-click copy button, and you can keep refining the input while you work; the result updates in place as you type.