Prompt splitter
Split long text into sequential chunks that fit a character limit, breaking on sensible boundaries.
Prompt splitter
Some boxes just won't take a wall of text. An AI chat truncates a long prompt, an SMS caps at a few hundred characters, a form field rejects anything over a set length, and a messaging app quietly cuts the rest. The prompt splitter takes one long passage and cuts it into a series of parts that each stay under a character limit you choose, so you can paste them one after another without losing a single word.
Set the maximum characters per part — 2000 by default, which suits most chat inputs — and the tool packs as much text as it can into each chunk without going over. It breaks on the boundary you prefer: whole paragraphs first, then sentences, then words. It only drops to a harder boundary when a single unit is itself longer than the limit, so a paragraph that fits stays whole, and a word is never cut in half unless that one word is longer than the entire limit.
Turn on part labels and each chunk is prefixed with a line like [Part 1/3], so whoever reads them — or the model you are prompting — knows the order and how many are still coming. Turn it off when you want the raw text alone. Parts are shown together, separated by a divider line, ready to copy in sequence.
Pick a network and its limit comes with it: X 280, Bluesky 300, Threads and Mastodon 500, LinkedIn 3000. Number the posts as [Part 1/3], a plain 1/3, the open-ended 1/, or a leading 🧵 1, before or after the text. Under a preset the numbering fits inside the platform's ceiling.
Everything runs locally in your browser. Your text is never uploaded, sent to a server or logged anywhere — the splitting is pure text math on your own device — so even a private draft, a confidential prompt or a client document stays entirely with you.