CleanThisText guide

How to remove duplicate lines without losing order

Understand case-insensitive matching, surviving spelling, and why the first occurrence stays.

Know the comparison rule

Remove Duplicate Lines compares a trimmed, lowercased version of each line. Apple, APPLE, and a line with spaces around apple therefore share one key. The first occurrence stays; later matches disappear. The result is not automatically alphabetized.

Do not use this rule for passwords, case-sensitive identifiers, or paths where capitalization distinguishes records. Matching lines is also not identity resolution: similar names may refer to different people.

Prepare one entry per line

A comma-separated row is still one entry. Use Trim Lines separately if outer whitespace is not meaningful. The duplicate tool trims for comparison, but does not generally normalize the surviving entry's internal spacing.

Remove Empty Lines separately if blanks should disappear. New York and New York remain distinct because their internal spacing differs. Decide whether that difference is meaningful before normalizing it.

Sort only after reviewing

Compare retained entries with the original list, including the earliest spelling of each repeated label. Sorting first changes which entry comes first, so deduplicate before sorting when that choice matters.

Keep ranked lists and chronological logs in their original order. If entries must remain aligned with adjacent spreadsheet columns, clean complete records in the spreadsheet rather than sorting an isolated column.

Worked example

Input

Apple
banana
APPLE
cherry
 banana

Result

Apple
banana
cherry

Matching ignores case and outer spaces. First-occurrence spelling and order survive.

Open Remove Duplicate Lines

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Use the related tools

List toolsRemove Duplicate LinesDeduplicate lines while preserving the first original occurrence.Text cleaningTrim LinesRemove spaces and tabs from the beginning and end of each line.List toolsRemove Empty LinesDelete blank and whitespace-only lines from pasted lists.List toolsAlphabetize LinesSort non-empty lines alphabetically from A-Z or Z-A.