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Dedupe Lines

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

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Send this tool's output straight into another tool.

Sort Lines

Sort the lines of a text alphabetically, naturally, by length, by numeric value or shuffled. Reverse the order with a switch, and optionally trim lines, drop blank lines and remove duplicates in the same pass.

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Text Case Converter

Convert text into every case at once: title case in the APA, AP, Chicago, MLA, Bluebook, AMA and NYT styles, sentence case, upper, lower, camelCase, snake_case, kebab-case and more.

textconverter

Word & Character Counter

Count words, characters, sentences, paragraphs, lines and more as you type, with estimated reading and speaking time.

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Dedupe Lines

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

textdev

Find and Replace

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

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Text Diff

Compare two texts and see every added, removed and changed line highlighted, side by side or inline, with the changed words marked within each line. Ignore case, whitespace or blank lines, read a summary of how much changed, and export the result as a unified diff.

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UUID Decoder

Paste a UUID to see what it carries: version, variant, and for time-based versions the exact timestamp, clock sequence and node. Also shows the raw bytes, the 128-bit integer and the URN form.

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Base64 Encoder & Decoder

Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

devconvertertext

Number Base Converter

Convert numbers between binary, octal, decimal, hexadecimal and any base up to 36. Type into any field and the others update as you go. Handles huge integers without losing precision and accepts 0x, 0b and 0o prefixes.

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About the Dedupe Lines Tool

This tool removes duplicate lines from a text. Paste a list and every line keeps only its first occurrence, in the original order, with a summary of how many duplicates were dropped.

It is built for the everyday cleanup jobs: merged email lists, exported keywords, log output, any list that has picked up repeats.

What you can do

  • Remove duplicate lines from a list while keeping the original order.
  • Ignore case, so Foo and foo count as the same line.
  • Ignore leading and trailing whitespace when comparing.
  • Remove blank lines in the same pass.
  • See how many lines went in, came out and were removed.

How to use the Dedupe Lines

  1. 1Paste your lines into the input on the left.
  2. 2Pick the comparison options: ignore case, ignore surrounding whitespace, remove blank lines.
  3. 3Read the deduplicated result on the right, then copy or download it.

What counts as a duplicate

By default two lines must match exactly, character for character. Turn on the options to loosen that: ignoring case treats different capitalizations as the same line, and ignoring whitespace lets an indented copy match a flush one. The kept line is always the first one as you typed it, the options only affect the comparison.

Blank lines are treated as structure, not content. They are never deduplicated against each other, so your paragraph breaks survive, but you can remove them all with the last option.

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Base64 Encoder & Decoder

Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

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Code Formatter

Format code in JavaScript, TypeScript, JSON, JSON5, HTML, Vue, CSS, SCSS, LESS, Markdown, YAML, GraphQL, XML and SQL. Pick tabs or spaces, set the indent width, and format the input in place with one click.

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Find and Replace

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

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HTML Entity Encoder & Decoder

Escape text into HTML entities or decode entities back to plain text. Choose named or numeric entities, escape only the unsafe characters or everything outside ASCII, and read the result live.

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Invisible Character Revealer

Reveal the characters you can't see in a text: zero-width spaces, non-breaking spaces, bidi marks, control characters and CRLF versus LF line endings. Inspect every occurrence and clean them out with a click.

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Log Redactor

Strip the sensitive bits out of a log or any text before sharing it: emails, IP and MAC addresses, file paths, UUIDs, timestamps, URLs, tokens and more. Pick what to redact and how it is replaced, with stars, a fixed character, a type label or a length-preserving mask.

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