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Category: Developer tools

CSV Cleaner

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Trim whitespace, drop empty rows and remove duplicates

Paste CSV data to trim whitespace from every cell, drop fully empty rows, normalize each row to the same number of columns and remove duplicate rows. Runs entirely in your browser.

Rows in5Rows out3Empty rows removed1Duplicates removed1
JSON
name,role,team
Ada Lovelace,Engineer,Blue
Grace Hopper,Admiral,Green
Alan Turing,Mathematician,Blue

Cleaning runs in your browser; the delimiter and header row use the same settings as the other CSV tools.

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

What this tool does

Each cleanup step can be turned on or off independently, so you can see exactly what changed. Trimming strips leading and trailing whitespace from every cell; normalizing pads short rows and truncates long ones to match the header; removing empty rows drops rows where every cell is blank; and deduplication removes rows that are exact repeats of an earlier row.

How to use it

  1. Paste CSV data into the input box, and set the delimiter and header row.
  2. Toggle which cleanup steps to apply: trim, normalize columns, remove empty rows, deduplicate.
  3. Copy the cleaned CSV, and check the row counts above the output.

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. Cleaning runs in JavaScript in your browser tab; nothing is sent to a server.
What counts as a duplicate row?
Two rows are duplicates when every cell matches exactly (or case-insensitively, if you turn that option on), after any trimming and column normalization has been applied.

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