Remove Duplicate Lines
Strip repeated lines from multiline text while keeping first-seen order.
Open Remove Duplicate Lines
Remove Extra Spaces / Clean Text
Clean up extra spaces and normalize plain text.
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Frequently asked questions
Common questions about this tool.
Whitespace includes spaces, tabs, and line breaks (and sometimes Unicode space characters). It affects layout, parsing, and whether two strings compare equal.
Copy-paste from PDFs, web pages, or chat often introduces double spaces and odd breaks. Cleaning reduces noise in diffs, CSV imports, and search.
By default the tool targets extra spaces and common whitespace issues, not necessarily every newline. Check the options for line-break behavior.
Yes, that is the typical behavior: consecutive spaces in a line are collapsed to a single space unless you choose a different mode.
Modern browsers handle Unicode. Rare combining characters or special spaces may need a quick visual check after cleaning.
NBSP (often from HTML) looks like a space but is a different character. It can break dedupe or search; some cleaners optionally replace NBSP with a normal space.
Trim usually removes leading and trailing whitespace on a line or string. Cleaning can also collapse internal runs of spaces or normalize tabs to spaces.
User input and file reads often include accidental outer whitespace. Trimming before validation avoids off-by-one bugs and rejected usernames or tokens.
Yes. YAML, Markdown tables, and aligned columns rely on spaces. Clean only plain prose or make a backup before aggressive normalization of technical formats.
Some characters can be composed multiple ways (e.g., é as one codepoint vs base + accent). NFC is a canonical form; advanced Unicode tools handle it beyond simple spaces.