Word Ladder Solver

How the solver works

The solver uses the same word list as the game: 5,395 four-letter words that are all linked, directly or through other words, to POOP. Two words are neighbours when they differ in exactly one position, so CARD and CORD are neighbours but CARD and DARK are not.

When you press Solve, the page runs a breadth-first search in your browser. It explores every word one move from the start, then every word two moves away, and so on, until it reaches the end word. Because it expands the search one layer at a time, the first route it finds is guaranteed to be as short as possible.

Many pairs have several routes of the same length. The solver counts all of them and shows the one made of the most familiar words, using the same frequency scores that pick the routes on the answer pages. Nothing is sent to a server; the whole search happens on your device.

Classic pairs, solved

These examples are calculated from the live dictionary every time the site is built, so the move counts always match what the tool above returns. The last column shows how many different routes share the same shortest length.

Use it without spoiling the daily puzzle

The solver will happily solve today's Poople, so it is worth deciding first what you want from it. If you only need a nudge, the Today Answer page gives graded hints before it shows the full path. If you have already finished, the solver is a good way to check whether your route was optimal and to see which words you missed.

A useful habit is to solve from your own last word instead of from the start word. If you are stuck at COOK, asking the solver for COOK to POOP tells you how far you really are without revealing the moves you have already worked out.

• HintsToday AnswerGraded hints first, then the shortest route for the current daily puzzle.
• GuideWord ladder strategyWorking backward, vowel pivots, and other habits that shorten routes.

What the solver cannot do

It only handles four-letter words, because that is the length Poople is built around. Longer ladders such as FLOUR to BREAD need a different dictionary and are out of scope here.

It only knows words that belong to Poople's connected word graph. Proper nouns, abbreviations and a short list of offensive words are excluded, and a handful of ordinary words such as EXAM or ENVY are missing because no chain of real words links them to POOP. If either word is not in the list, the solver tells you which one.

Some shortest routes pass through uncommon dictionary words. That is a property of the language rather than a bug: a four-move route through TEAD may beat a five-move route through everyday words. When you play, a slightly longer route made of words you know is still a fine result.

Ideas for teachers and puzzle makers

Word ladders are a classic spelling and vocabulary exercise. The solver makes it quick to check that a pair you want to set actually has a route, and the move count gives a rough difficulty level: three or four moves suits younger players, while six or more is a real challenge for adults.

Pairs with many equally short routes are forgiving, because students can find different valid answers. Pairs with only one or two routes are better for competitions, since there is a single best answer to aim for. To turn a start word into a puzzle for a friend, use the Challenge button on the game page.