Observed arrival · 2026-09-20
Cryptarithm: Arithmetic Puzzles with a Logic-Grid Soul
A free browser puzzle game that hides arithmetic digits behind missing squares or letters.
○Open
⊠Login
$Paid
†Ads
✦Pretty
●Pro
◎Niche
◉Human
⚑Risk
ƒJS
- For
- Arithmetic learners, puzzle solvers, and teachers
- Worth noticing
- Generated puzzles are checked for unique solutions, including every intermediate arithmetic row.
Field notes
The puzzle engine supports both repeated-digit arithmetic and letter-based cryptarithms, where matching letters share a value and different letters cannot. The page describes server-generated problems, unique-solution checking, exact division, and a curated source for some Hard letter puzzles. A completed or in-progress puzzle can also be turned into a clean PNG or a shareable reconstruction link.
Observed signals
Read the marks
Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
One card from the complete issue