Decodex
Decode the day's quotation, with its author as your first clue.
Every day: One dated quotation a day, the same for everyone on the website, encrypted with a letter-substitution cipher; past games are playable, and the iOS app has a separate daily puzzle of its own. New puzzle: Once a day; the site does not state the time.

Decodex is a daily cryptogram. Each day a quotation is shown with every letter swapped for another, and you guess the real letter behind each code letter until the whole quote reads. The author is shown to get you started, a few helps unlock letters, and a timer and streak keep score.
About Decodex
Decodex is a cryptogram puzzle made by Áron Csatlós, playable on the web and in an iPhone and iPad app. The website's daily challenge is a quotation encrypted with a simple substitution cipher: each letter in the quote has been replaced by a different one, consistently, with spaces and punctuation left as they are.
You click a code letter and type the letter you think it stands for, and it fills in everywhere that code letter appears. The author of the quote is shown at the top as a first hint, which can tell you the era and the kind of words to expect. If you are stuck, a small set of helps can each unlock a letter, and you can surrender if the quote beats you. A timer runs while you play, and the game keeps a streak of days solved.
Each day's quote is dated, and a Past Games page lets you go back to earlier ones. There are also Campaigns of themed puzzles, and the app has its own daily puzzle that differs from the website's, plus app-only campaigns. The site carries ads, which donors can switch off with a code. It suits players of the newspaper cryptoquote and anyone who liked Decipher or Cyphr.
How to play Decodex
- Open Decodex and read the author shown at the top of the puzzle.
- Click a code letter and type the letter you think it stands for.
- Watch it fill in across the quote, and use short words and patterns to find the next letter.
- Tap an available help to unlock a letter when you are stuck.
- Decode every letter to finish, then share your time.
Tips
- Start with one-letter words, which are almost always A or I, and with apostrophes.
- Think about the author: a philosopher and a comedian use different words.
- Look for repeated three-letter words, which are often THE or AND.
- Keep helps for the end, when one letter can unlock several words.
Questions
Is the app puzzle the same as the website's?
No. The app has a different daily puzzle from the website, as well as its own campaigns.
Can I play past puzzles?
Yes, from the Past Games page.
How do I remove ads?
Donate on Ko-fi to receive a code, then enter it on the site.
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