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Thread Splitter

Split a long text into numbered posts that fit a character limit. Pick a preset for X, Threads, Mastodon or Bluesky or set your own limit, choose the numbering style, and keep words or paragraphs intact. Copy each post on its own or all at once.

Everything runs locally in your browser. Your data never leaves your device.

Limit and numbering

Numbering counts toward the limit. Characters are counted as Unicode code points, so an emoji counts as one.

Posts

Paste your text above and the numbered posts appear here.

Next steps

Send this tool's output straight into another tool.

Word & Character Counter

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

text

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

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.

textdev

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.

textdev

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.

devuuid

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.

devconvertercalculator

Scientific Notation Converter

Convert between scientific notation and full numbers as you type. Reads 1.23e5, 1.23 × 10^5 and plain numbers, shows the value written out, in normalized scientific notation and in engineering notation, and can round to any number of significant digits.

convertercalculator

About the Thread Splitter Tool

This tool splits a long text into a numbered thread of posts that each fit a character limit. Pick a preset for X (280), Bluesky (300), Mastodon (500) or Threads (500), or set your own limit, then choose how the posts are numbered and copy them one by one or all at once.

The splitter never cuts a word in half. It prefers to end a post at a sentence or line break and falls back to the last word that fits. Numbering counts toward the limit, including the digits of the final total, so a post ending in 9/12 still fits its platform.

What you can do

  • Split a long text into tweets for an X thread.
  • Split text into posts for Mastodon, Bluesky or Threads.
  • Number posts as 1/5, (1/5), a 1/ prefix or a 🧵 style.
  • Set a custom character limit for any other platform.
  • Start a new post at every blank line to keep paragraphs intact.
  • Copy each post on its own, or copy or download the whole thread.

How to use the Thread Splitter

  1. 1Paste your text into the input box.
  2. 2Pick a platform preset or enter a custom character limit.
  3. 3Choose a numbering style and decide whether blank lines start a new post.
  4. 4Copy each post into your app, or copy or download the whole thread.

How characters are counted

Characters are counted as Unicode code points, so an emoji or any other character outside the basic plane counts as one, not two. This matches how Mastodon and Bluesky count and is a close match for X and Threads. X additionally counts every link as 23 characters and some CJK characters as two, which this tool does not model, so leave a little headroom in link-heavy posts.

A single word or link that is longer than the limit is never broken up. It gets its own post, which is marked as over the limit so you can shorten it or raise the limit. To check other statistics of your text before posting, run it through the Word & Character Counter.

Related tools

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

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.

devtextjsonyaml

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.

textdev

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.

devconvertertext

Image to Text (OCR)

Read the text out of a screenshot, photo or scan with OCR. Pick the language, watch the recognition progress, review the result with per-word confidence, and copy or download the extracted text.

mediaimagetextconverter