थ्रेड स्प्लिटर.

Up to 50,000 characters. Nothing is posted. Everything is calculated in your browser; nothing you type is uploaded.

Text is split at paragraph breaks, then sentence ends, then between words. Room for the numbering is reserved, and X’s weighted counting is used for X.

A three-paragraph text splits into 3 posts of up to 280 characters, numbered 1/3 to 3/3.