Paste a list to see which lines repeat and how often each one appears. Filter, sort, copy the unique lines, or download the results.
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DetailsHow this duplicate line finder counts repeats
Paste a list, a column copied from a spreadsheet, or any text with one item per line. The tool treats each line as an item, counts how many times each item appears, and shows the results in a table. Lines that appear more than once are highlighted.
Use the Filter menu to show only repeated lines or only lines that appear once. Use Copy lines to get each distinct line once, which is the usual way to remove duplicates. Copy with counts pastes the same results as two tab-separated columns, so they land in separate cells in Excel or Google Sheets.
All processing happens in your browser. Nothing you paste is uploaded.
When you need to count or remove repeats
Cleaning a mailing list
Paste a list of email addresses to see which ones appear more than once. Copy lines gives you the list with each address once.
Checking IDs or product codes
Paste one column of member IDs or SKUs. Any code that appears twice is marked Repeated, with its count beside it.
Reading repeated log messages
Paste lines from a server or error log to see which messages occur most often. Keep the default Most repeats first sort to find the top ones.
Trimming a keyword or tag list
Paste your keywords or tags, one per line, and copy back the unique list. Turn Case-sensitive off to merge Apple and apple.
Steps to count repeated lines
- Paste your list into the input box, one item per line. A single column copied from Excel or Google Sheets works too.
- Check the three comparison settings. Case-sensitive, Trim spaces, and Skip blank lines are on by default. Change them if your data needs it.
- Pick a filter and a sort order. Then click Copy lines for a list without repeats, Copy with counts for the numbers, or Download CSV for a file.
Note: Results update as you paste or change a setting. There is no button to run the check.
How each line is compared
- Line breaks: the text is split at each line break. Windows (CRLF) and Unix (LF) line breaks are both handled.
- Capital letters: with Case-sensitive on, Apple and apple are different lines. With it off, they match, and the row shows the spelling that appeared first.
- Spaces: Trim spaces removes spaces and tabs at the start and end of each line. Spaces between words are kept.
- Blank lines: with Skip blank lines on, empty lines are not counted. If Trim spaces is off, a line that holds only spaces is not empty, so it is counted.
- Order: lines with the same count keep the order in which they first appeared, even when you sort by count.
Settings and what they change
Each setting, its default, and the change it makes. You can change any of them at any time.
| Setting | Default | What it changes |
|---|---|---|
| Case-sensitive | On | When on, Apple and apple count as different lines |
| Trim spaces | On | Removes leading and trailing spaces and tabs before comparing |
| Skip blank lines | On | Leaves empty lines out of the counts |
| Sort | Most repeats first | Changes row order; choose Original order to keep your list's order |
| Filter | All lines | Shows all lines, only repeated lines, or only lines that appear once |
| Search results | Empty | Narrows the rows shown and the CSV, but not the stats cards |
Changing Case-sensitive or Trim spaces can change the counts, because they decide which lines are treated as the same. The stats cards always count the whole list, so a search does not change them.
Repeated items in lists, logs, and copied text
Most duplicate checks come down to two decisions: what counts as the same item, and what you do with the repeats.
Checking a column of values from a spreadsheet
Copy a column from Excel or Google Sheets and paste it into the box. Each cell becomes one line, so the tool counts how often each value appears down the column. Check the Repeated number first, then copy the lines you want to keep.
Deciding whether Apple and apple are the same item
For names, email addresses, and tags, you usually want the same item in different capitals counted once, so turn Case-sensitive off. For codes or passwords, where case matters, leave it on. The first spelling found is the one that appears in the results.
Keeping the original order after removing repeats
Sorting by repeat count moves lines around, which breaks a list that should stay in order. Choose Original order, leave the filter on All lines, and click Copy lines. Each distinct line appears once, in the order it first showed up.
Mistakes that hide or inflate duplicate counts
Near-duplicates counted as different lines
A name with two spaces between words, such as Jane Smith, looks the same on screen as Jane Smith. The tool does not merge spaces inside a line, so the two are counted separately.
💡 See the solution▼
Blank lines inflating the total
Copied text often has empty lines between paragraphs. If Skip blank lines is off, each empty line counts as an item and appears as a row.
💡 See the solution▼
Reading the Repeated number as the count of extra copies
Repeated counts distinct lines that appear more than once. A line that appears four times is one repeated value, not three extra copies.
💡 See the solution▼
A sorted list that loses its original order
The default sort puts the most common lines first. If you copy the result right away, the list is no longer in the order you pasted it.
💡 See the solution▼
Questions about removing repeats and counting lines
Q.Is my list sent to a server?
A. No. The tool compares lines with JavaScript in your browser, and the code has no upload step. The list stays in the page while it is open, and closing or reloading the page clears it.
Q.How do I remove duplicate lines and keep the original order?
A. Set Sort to Original order and Filter to All lines, then click Copy lines. Each distinct line appears once, in the order it first showed up in your list.
Q.Does the tool count blank lines?
A. Not by default. Skip blank lines is on, so empty lines are left out of the counts. Turn it off if you want empty lines counted as items.
Q.Are uppercase and lowercase letters treated as the same?
A. Not by default. Case-sensitive is on, so Apple and apple count as two different lines. Turn it off to merge them. The row then shows the spelling that appeared first in your list.
Q.What does Trim spaces change?
A. It removes spaces and tabs at the start and end of each line before comparing, so 'apple ' and 'apple' match. Spaces inside a line are not changed, so 'red apple' with two spaces and 'red apple' still count as different.
Q.What does the Repeated number mean?
A. It counts distinct lines that appear more than once. A line that appears four times adds one to Repeated, not three. The Lines number counts every line that was checked, and Distinct counts each unique line once.
Q.Can I count repeated sentences in an essay?
A. This tool compares whole lines. To check sentences, put one sentence on each line first, then paste the text.
Q.Can I download the results as a file?
A. Yes. Download CSV exports the rows you see, with a Line column and a Count column. If you have typed a search or chosen a filter, only the matching rows are included.
Q.Is there a limit on the number of lines?
A. The tool does not set a limit. Every row is drawn on the page, so a very long list can make the page slow on an older device.
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