Word ladder solver

Fast, exact route finding

How the word ladder solver works

A word ladder—also called a word chain, word morph, or doublet—connects two words by changing one letter at a time. Every intermediate step must be a dictionary word, and the word length stays fixed for the whole route.

This solver treats each word as a point in a graph. Two points connect when their words differ in exactly one position. Breadth-first search explores those connections one move at a time, so the first completed route uses the fewest moves available within this tool’s dictionary.

1. Choose a word length. Select three, four, or five letters.
2. Enter matching endpoints. Add a start word and target word with the same length.
3. Review the route. Select Solve ladder to see each valid one-letter change in sequence.

A worked four-letter route

Word ladder example: COLD to WARM

One minimum route is COLD → CORD → CARD → WARD → WARM. COLD becomes CORD by changing L to R; CORD becomes CARD by changing O to A; CARD becomes WARD by changing C to W; and WARD becomes WARM by changing D to M. Every rung is four letters long and every move changes exactly one position.

A different dictionary may contain another route with the same number of moves. That does not make either answer wrong: many word ladders have multiple shortest solutions.

Understand the result

What to do when no word ladder is found

“No path” does not necessarily mean the spelling is impossible in every English dictionary. Word lists vary, uncommon forms may be excluded, and some valid words sit in disconnected parts of the word graph. Check the spelling and length first, then try a more familiar endpoint.

If you need possible bridge words, use the Word Finder to explore a pattern. To make a fresh, pre-checked challenge instead, open the word ladder generator.