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Tools / In-browser CSV & Excel data cleaner

In-browser CSV & Excel data cleaner

Clean and standardize messy CSV, TSV, and copied spreadsheet tables in your browser. Features whitespace trimming, duplicate row deduplication, blank row removal, ISO date standardization, and phone number formatting.

Runs entirely in your browser

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About this tool

Messy spreadsheet data — stray spaces, duplicate rows, blank lines, dates in a dozen formats — is tedious to fix by hand. This cleaner standardises CSV, TSV and copied spreadsheet tables in your browser: it trims whitespace, removes duplicate and blank rows, standardises dates to ISO format, and normalises phone numbers, giving you tidy, consistent data.

Cleaning happens entirely client-side, which matters because spreadsheets often contain personal or business data you would not want to upload to an online tool. You paste or load the table, apply the cleaning steps, and export the result.

Use it before importing data into another system, merging exports from different sources, or analysing a table that arrived in inconsistent shape. Consistent formatting prevents the errors that dirty data causes downstream.

Frequently asked questions

What does the data cleaner do?
It trims whitespace, removes duplicate and blank rows, standardises dates to a consistent ISO format, and normalises phone numbers in CSV, TSV or copied spreadsheet tables.
Is my spreadsheet data uploaded?
No. Cleaning happens entirely in your browser, so personal or business data stays on your device.
What formats can it clean?
CSV, TSV and tables copied directly from a spreadsheet, which you can paste or load and then export once cleaned.
Why standardise dates?
Mixed date formats cause errors when importing or sorting. Converting them to a single ISO format makes the data consistent and reliable downstream.
When should I use it?
Before importing into another system, merging exports from different sources, or analysing data that arrived with inconsistent formatting.

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