Contact List CSV Cleaner
Clean a contacts CSV: remove duplicate emails, trim spaces, fix name capitalisation and drop invalid addresses, with spreadsheet safe output.
Runs on your device
Result
Results appear here after you select “Clean list”.
What it does
Before importing leads into a CRM or email tool, remove duplicates and broken addresses so you do not pay for them twice or damage your sender reputation.
How to use it
- Paste the CSV including the header row.
- Name the email column if it is not called "email".
- Clean and download.
Example
The example fills in realistic values and runs the tool. Select Try an example above to see it.
When it helps
- Preparing CRM imports.
- Merging lists from events.
- Reducing bounce rates.
Questions
Which duplicate is kept?
The first row for each email address.
Why do some cells start with an apostrophe?
Cells beginning with an equals, plus, minus or at sign are prefixed so spreadsheets do not run them as formulas.
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