Text Tools

Remove Duplicate Lines

Clean a list by removing repeated lines while keeping the first occurrence and original order. Optionally ignore case, trim each line or remove blank lines, privately in your browser.

Your content stays on your device Free, with no account
Keep the useful. Lose the repeats. Processed on your device
Up to 200,000 text units and 20,000 lines. Original order is kept.

Ready. Choose your options and remove duplicates.

Case-insensitive matching keeps the first spelling. Trimming changes the spacing in the result. Your original stays unchanged.

A FEW SIMPLE STEPS

How to use Remove Duplicate Lines

  1. Paste a list with one entry per line. The original text stays in the input.
  2. Choose whether to ignore letter case, trim leading/trailing whitespace, or remove blank lines. Options are off by default.
  3. Select Remove duplicates. Review the cleaned list and the totals for kept, duplicate and removed blank lines.
  4. Copy or download the cleaned text. Editing the input or options clears the old result so you can run it again.
PRIVATE BY DESIGN

Why use this tool?

Your list is processed on your device with no uploads, account, libraries or browser storage. The first occurrence of every matching line is kept, without sorting your list. You can compare the cleaned result with the untouched original.

Tool inputs stay in your browser. Only your theme preference is saved on this device.

A few things worth knowing

Which copy of a duplicate line is kept?

The first occurrence is kept, and the original relative order stays unchanged. By default, matching is exact, including letter case and whitespace. Ignore case changes matching only, so the first spelling is retained.

Does trimming change the result?

Yes. With Trim enabled, leading and trailing whitespace is removed from every line before comparison and output. Spaces inside the line remain unchanged. Without trimming, differently spaced lines remain distinct.

How are blank lines handled?

By default, repeated identical blank lines are deduplicated like other lines. Whitespace-only lines are distinct unless trimming is enabled. Remove blank lines drops empty and whitespace-only lines before duplicate matching, and counts them separately from duplicate removals.

How are final line breaks and line totals handled?

An ending newline terminates the final line and is not counted as an additional blank entry. If the input ends with a newline and at least one line is kept, the result retains an ending newline. CRLF and CR endings are normalized to LF. These list-entry counts can differ from counters that include a trailing empty line.

Can it compare emails, URLs or multilingual text?

It compares complete text lines rather than validating their meaning. Unicode lowercase mappings are used when ignoring case. It does not normalize accents, rewrite URLs, validate addresses or apply locale-specific matching.

What are the limits?

Each list can contain up to 200,000 UTF-16 text units and 20,000 lines. Some emoji use multiple units. Oversized input is preserved, but processing is unavailable until it is shortened. Empty results have no download; clear removes both input and result.