Duplicate Email Finder
A duplicate email finder shows which addresses appear more than once in a list and gives you the list back with each address once. Paste a list or drop Excel, CSV and text files: repeats are matched regardless of capital letters and spacing, across every file, and Gmail aliases can be merged too. Everything runs in your browser.
Paste a list or drop your files. See every repeat, get a clean list.
100% free • No signup • Runs in your browser
How to use the Duplicate Email Finder
- 1
Paste or drop
Paste a list of addresses, or drop Excel, CSV and text files. Add several files to find the addresses they share.
- 2
Review the duplicates
Each repeated address is listed with how many times it appears and where. Turn on alias merging to catch Gmail dots and +tags.
- 3
Copy the clean list
Copy the deduplicated list or download it as a CSV, in the original order or A to Z.
What counts as a duplicate
Two entries are duplicates when they are the same address once capital letters, spaces and surrounding text are set aside. With “Treat aliases as duplicates” on, addresses that deliver to the same inbox are merged as well.
| These two entries | Why | Duplicate? | With aliases on |
|---|---|---|---|
| jane@acme.comJANE@Acme.com | Capital letters | Yes | Yes |
| jane@acme.comJane Doe <jane@acme.com> | A name around the address | Yes | Yes |
| jane.doe@gmail.comjanedoe@gmail.com | Gmail ignores dots | No | Yes |
| jane@gmail.comjane@googlemail.com | googlemail.com is Gmail | No | Yes |
| tom@acme.comtom+news@acme.com | A +tag reaches the same inbox | No | Yes |
| jane.doe@acme.comjanedoe@acme.com | Dots matter outside Gmail | No | No |
The finder removes repeats and anything that isn't shaped like an email address. It doesn't check whether each mailbox exists. To pull addresses out of PDFs, Word documents and other files first, use the Email Extractor.
Duplicate emails in Excel, CSV and lists
Frequently Asked Questions
Is the duplicate email finder case sensitive?
No. Jane@Acme.com and jane@acme.com are treated as the same address, because mail providers deliver them to the same inbox in practice. The clean list is in lowercase.
Can I find duplicates between two lists?
Yes. Paste one list and drop the other as a file, or drop both files. Addresses in both are listed as duplicates, along with where each one appears.
What does "Treat aliases as duplicates" do?
It merges addresses that reach the same inbox. Gmail ignores dots, so jane.doe@gmail.com is janedoe@gmail.com, and most providers deliver jane+news@acme.com to jane@acme.com. It's off by default because some mail systems treat these as separate mailboxes.
Which copy is kept when there are duplicates?
The first one. The clean list keeps each address where it first appeared and drops the later copies. Choose A to Z to sort the list instead.
How many emails can it check?
Paste a long list, or drop up to 20 files of up to 25 MB each. The page shows the first 500 addresses of each list, and copying or downloading the CSV includes every one.
Is my email list uploaded?
No. The list and any files are processed in your browser and never sent to our servers or stored.