Encode or decode with a 5x5 Polybius square, with an optional keyed alphabet and GitHub-style coordinate pairs. 5x5 SQUAREKEYED SQUAREJ FOLDS TO ICLIENT-SIDE
The Polybius square is 5×5, so J folds into I by default — a 5×5 grid has 25 cells and the alphabet has 26 letters. Every letter becomes a row/column pair like 23.
Spell any number out in words, and hear it spoken aloud.
Search and copy emoji by name, with skin-tone and category filters.
Build a table of contents from Markdown headings with GitHub-accurate anchor slugs, including the -1 suffix on duplicate headings.
One input, fourteen cases: title, sentence, camelCase, PascalCase, kebab, snake, dot and more.
Devine, Robinson, Miller and Hamwi side by side, plus the healthy BMI band.
Reduce a ratio with GCD, scale it, split a whole, and convert seven unit pairs.
Percent change, the reverse, percent-of, and compound growth over N periods.
A scale ladder from 1 m to the observable universe: how many of a reference object fit.
