Remove Duplicate Lines

Strip duplicate lines, trim blanks and optionally sort the result.

Remove Duplicate Lines From Any List

Merged exports, concatenated logs and copied spreadsheet columns all accumulate duplicates. Deduplicating them by eye is slow and unreliable, and spreadsheet functions for the job are fiddly enough that most people give up and live with the mess.

Paste your list and the duplicates disappear immediately. You control whether case matters, whether lines are trimmed before comparison — which catches duplicates that differ only by trailing whitespace — and how the result is ordered.

Key features

  • Live counts — lines in, lines out and how many were removed.
  • Case sensitivity toggle — treat "Apple" and "apple" as the same entry or as distinct ones.
  • Trim before comparing — catches duplicates that differ only by leading or trailing whitespace.
  • Five sort orders — original, A→Z, Z→A, by length, or by how often each line appeared.
  • Invert mode — show only the lines that were duplicated, which is how you audit a list.
  • Frequency table — the most-repeated lines with their counts.
100% client-side — no data leaves your machine

This tool runs entirely inside your browser using native Web APIs. Your files and text are never uploaded to a server, never logged and never shared with third parties.

How to use: Remove Duplicate Lines

  1. Paste your list
    One entry per line — emails, IDs, URLs, keywords, anything.
  2. Set comparison options
    Trimming and case-insensitive matching catch near-duplicates that an exact comparison would miss.
  3. Choose a sort order
    Keep the original order, sort alphabetically, or sort by frequency to surface the most common entries.
  4. Copy the result
    Or switch to invert mode first to review exactly which entries were duplicated.

Technical specifications

Processing locationEntirely in your browser — no server round trip
Data uploadedNone. Files and text never leave your device
PriceFree — no account, no trial, no usage cap
CategoryText
Works offlineYes, once the page has loaded
Browser supportChrome 90+, Edge 90+, Firefox 90+, Safari 15+
Interface languagesEnglish, 中文, हिन्दी, Español, العربية

Frequently asked questions

Does it keep the first or last occurrence?

The first. In original-order mode the output preserves the sequence of first appearances, so the list stays recognisable rather than being reshuffled.

Why are "Apple" and "apple" treated differently?

Because case sensitivity is on by default, which is correct for IDs, codes and anything case-significant. Untick it for names, emails and general text where case is incidental.

How do I find which entries were duplicated?

Tick "Show only the duplicates". The output becomes the list of entries that appeared more than once, and the table below ranks them by frequency.

Is there a size limit?

No hard limit. Lists of a few hundred thousand lines process in well under a second because everything runs locally with no upload step.

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