About ONE LETTER

ONE LETTER is a free daily word puzzle. Each day brings a new challenge: transform a four-letter start word into a target four-letter word by changing exactly one letter at a time, with every intermediate step forming a valid English word. The goal is to reach the target in as few moves as possible and compare your route to the shortest possible solution.

The game is designed for anyone who enjoys wordplay, vocabulary challenges, and daily brain teasers. Whether you are a casual player looking for a quick daily ritual or a puzzle enthusiast who wants to optimize every route and maintain a streak, ONE LETTER gives you a fresh, fair puzzle every single day. Your progress is saved automatically on your device, and you can share your results spoiler-free to challenge friends.

ONE LETTER is built and maintained by the ONE LETTER team. The app is created with a mobile-first, accessible design, runs entirely in the browser, and requires no account to play. An optional analytics layer collects anonymous, device-based metrics to help us understand how the game is played — it never collects names, emails, or any other personal information.

The rules are simple but the puzzles reward careful thinking: backtracking is allowed and counts as a new move, hints mark an attempt as assisted, and a new puzzle appears every day at UTC midnight. Whether you are sharpening your vocabulary on a commute or competing for the shortest route, ONE LETTER offers a satisfying daily challenge.