How to do it?
- 1.
Paste your list
Paste text into the top box with one item (email, name, number) per line. A spreadsheet column works too.
- 2.
Pick an operation
Click “Remove duplicates” or another operation: sort A-Z or Z-A, sort numerically, reverse, shuffle, trim, number lines, add a prefix/suffix or count occurrences.
- 3.
Set comparison options
Turn on “Ignore case” and “Ignore spaces” if “John Smith” and “john smith ” should count as the same item; “Skip empty lines” drops blank lines from the result.
- 4.
Copy the result
See how many lines were removed, then copy, download as .txt, or click “Use as input” to chain the next operation.
How duplicate removal works
The tool keeps the first occurrence of each line and drops later ones, preserving the original order. From “apple, Apple, pear, apple , plum” an exact comparison keeps 4 items, because a different capital letter or a trailing space is different text. With Ignore case and Ignore spaces on, 3 remain: “apple, pear, plum”.
Ignoring spaces trims both ends of each line and treats repeated spaces as one - the most common source of hidden duplicates when copying from spreadsheets and PDFs. The kept line is shown exactly as it was first written; the options only affect the comparison. Statistics above the result show input lines, unique lines, duplicates and empty lines.
Natural and locale-aware sorting
Sorting uses Intl.Collator, so accented letters sort next to their base letters (é next to e) and numbers inside text compare as numbers: “file1, file2, file10” instead of the computer-style “file1, file10, file2”. With “Ignore case” on, “apple” and “Apple” are treated as equal while sorting.
Sort numerically orders lines by the first number found anywhere in the line, e.g. “Item 12.5 kg” → 12.5 and “-3 °C” → −3. Lines without a number go last in their original order. Thousands written with a space (“1 200”) are read as 1200, but a comma is treated as a decimal separator, so “1,200” sorts as 1.2 - remove thousands commas first if your list uses them.
Other operations
| Operation | What it does | Example |
|---|---|---|
| Number lines | adds “1. ”, “1) ”, a tab or “1 - ”; the start number is configurable | milk → 1. milk |
| Add prefix/suffix | adds text at the start and end of every line | prefix ', suffix ', → 'ab12', for an SQL IN (…) list |
| Count occurrences | number of times each item appears, most frequent first, as “count [tab] line” | 3 apple, 1 pear |
| Trim spaces | removes leading/trailing spaces and collapses repeated spaces and tabs | “ a b ” → “a b” |
| Remove empty lines | drops lines that are empty or contain only spaces | - |
| Reverse order | last line becomes first | - |
| Shuffle | random order (Fisher-Yates); “Shuffle again” re-draws | - |
Practical examples
- Mailing list: paste emails from several exports, turn on Ignore case (email addresses are case-insensitive) and Ignore spaces, then Remove duplicates.
- Survey answers: use Count occurrences to see which answer was given most often, then paste the tab-separated result into a spreadsheet as two columns.
- Keyword list: Trim spaces → Remove duplicates → Sort A-Z, chaining the steps with “Use as input”.
- Random order: Shuffle a class list for presentation order, or put the names on the wheel spinner for a live draw.
To compare two versions of a list line by line, use the diff checker; to count characters or words, the character counter.
Frequently asked questions
How do I remove duplicate lines from a list?
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Are “Smith” and “smith” duplicates?
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Does the order change?
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How do I remove empty lines?
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Why does “file10” come after “file9”?
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How many lines can I paste?
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Is my list uploaded anywhere?
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