Normalize Date Formats in a Spreadsheet

One column holds 03/04/2024, 2024-03-05 and 6 March 2024: sorting, filtering and every chart built on it become unreliable. Add the Normalize dates step, pick the column, and every value comes out in a single format.

Choose ISO (2024-03-05) for databases and scripts, or a day-first or month-first style for people. Values that can only be read one way are resolved automatically; when a date like 03/04/2024 is genuinely ambiguous, tell the tool which order your file uses and the rest are converted too.

Clean a Table

Remove duplicates, trim spaces, split columns, find and replace, fill blank cells. Build a cleaning recipe and export the result. The file never leaves your browser.

Your data never leaves this browser

The file is parsed, previewed and charted on your own device. Nothing is uploaded — not even a sample. Close the tab and the data is gone.

Or paste table text
Import a file to get started. Everything runs locally.

How it works

  1. 1.Import the table to clean (Excel, CSV, TSV or JSON, or paste) — nothing is uploaded.
  2. 2.Add the steps you need from the list: delete empty rows, trim spaces, remove duplicates, find and replace, split or merge columns, normalise dates, numbers and phone numbers.
  3. 3.Order the steps with the arrows, or ask the AI for a plan and apply the steps it suggests.
  4. 4.Press Clean the table: every step reports how many rows and cells it changed, then export the result as CSV or Excel.

Frequently asked questions

What happens to ambiguous dates like 03/04/2024?
On the automatic setting they are left untouched, because day-first and month-first are both plausible. Pick day-first or month-first for the column and those values are converted as well.
Are times and unreadable values preserved?
A value that includes a time keeps its time after conversion. Anything the tool cannot read stays exactly as it was, so you can filter for the leftovers instead of losing them.

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