How to play Word Ladder

Word Ladder is a gentle puzzle invented by Lewis Carroll back in 1877, and it still makes for a wonderfully satisfying few minutes. You are given a start word and a target word, both four letters long, and your task is to climb from one to the other a single rung at a time. Each rung changes just one letter, and every word along the way has to be a genuine English word.

Goal

Turn the start word into the target word, changing exactly one letter per step and keeping every word real and four letters long. There is no limit on how many steps you take, but the puzzle quietly tracks the shortest possible path, so part of the fun is trying to match — or beat your previous effort toward — that ideal route.

How to play

• Type a four-letter word that differs from your current word by exactly one letter and press Enter.
• If it is a valid word and differs by a single letter, it is added as the next rung of the ladder.
• The game will tell you if a word is the wrong length, identical to the last one, more than one letter different, or not in the word list.
• Use undo to step back a rung if you wander down a dead end, and reach the target word to complete the ladder.
• Stuck for good? The give-up button reveals the shortest possible path from start to target.

Example

COLD → CORD → CARD → CARE → CASE → BASE — five steps from COLD to BASE, changing one letter each time.

Strategy and tips

Begin by noting which letters differ between the start and target words; those are the ones you ultimately need to change, and the others you generally want to leave alone. Work toward fixing one position at a time while keeping the rest of the word stable. Vowels are the most flexible letters to swap, so they often open up the next rung when you feel boxed in. Do not fret if the most natural in-between word sends you on a small detour — a winding ladder still counts, and the give-up reveal is always there to show you the tidiest route once you are done exploring.