FreeFree duplicate check

Remove duplicate emails from a PST.

Find copies of the same message and write a clean PST that keeps one of each. Every duplicate is confirmed by a full comparison before it is left out.

Nothing uploadedEvery result verifiedOriginal never changed
PST

Drop the PST to clean up

or choose it.

Read on this computerNothing uploaded
    Same sender, recipients, subject, sent time, Message-ID, body and attachments, even if stored differently.
    A copy in another folder is kept.
    The result is checked before you can save it.
    Working
    Elapsed 0 s · your file stays on this computer
    How it works

    3 steps, nothing to install.

    1

    Choose the rule

    Same content (recommended) or exact copies only; in the same folder or anywhere in the file.

    2

    Count them for free

    See how many duplicates there are before anything is written.

    3

    Write a clean copy

    A new PST keeps one copy of each message. The original stays as it was.

    Verified, not assumed

    Checked before you save it.

    The engine checks its own work. The result is read back from storage and compared with your original, and the report you can download lists every check.

    Every duplicate confirmed by a full comparison, not just a hash
    The first copy in folder order is kept
    The new file is read back and checked
    The original file is unchanged
    FAQ

    Questions, answered.

    Does it delete anything from my PST?

    No. It writes a new PST without the duplicates; the original is untouched.

    Why are duplicates in my PST?

    Repeated imports, sync problems and merged archives are the usual causes.

    Is my file uploaded?

    No. The engine runs inside your browser tab and reads the file from your disk. Results are written to your browser's private storage until you save them. Nothing is sent to a server.

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