In a letter sum, every letter stands for a digit. The same letter is always the same digit, different letters are different digits, and no number begins with 0.
Word sums are the classics, where the words themselves make a sentence — the most famous is SEND + MORE = MONEY. Code sums give you two or three sums written in the same code; crack it, and reading the letters for 0, 1, 2 … 9 spells a hidden ten-letter word.
Start from the right: the units column tells you about the last letters, and any carry moves left. When two numbers add up to a longer answer, the extra first letter must be 1.
Replace each letter with a digit — different letters, different digits, no leading zeros — so that every sum is correct.
The full guide, with a worked example and common mistakes: How to play Letter Sums.
All the sums share one code. When you’ve matched every letter to a digit, read the letters for 0, 1, 2 … 9 — they spell a ten-letter word.
Yes — code sums at higher levels use − and ×, and the solver accepts them too.
Yes — every puzzle here is checked to have exactly one solution.
Open the Letter Sums Solver, type the sums and press Solve.