Crossmath Cache Builder

Build a Crossmath geocache. Fill the blanks so every row and every column is a true equation.

Free, just a username and passphrase, no email. Caches you build show up in My Caches so you can reopen and edit them without hunting for the edit link, and watch plays and wins. The same account syncs My Puzzle Texts across devices and manages your short links.

My Caches

Crossmath is an arithmetic cross-grid. Every row and every column is an equation, and the bottom-right number has to satisfy both at once. Some cells are blank, and the finder taps digits from 1 to 9 to fill them. Clearing every round you pick unlocks your final coordinates or a keyword. You write no puzzle here: each board is generated and checked on our server, so the solution never sits in the page.

A 3 by 3 board with two blanks. Reading across, 10 minus something is something. Reading down, 10 minus 7 is 3. Only one pair of digits makes every line true at the same time.

Do not put sensitive, personal, or inappropriate content in a cache. Anything you create here is public to anyone with the link, and you are responsible for what you publish. Keep a copy of your edit key, it is the only way to change or delete your cache later.

Cache

Cache name

GC code (optional)

Your email (optional)

Only the site admin can see this, in case they need to reach you about your cache. Never shown to players.

Intro message (shown before play)

Intro image URL (optional)

Hint (optional)

Puzzle settings

Rounds to clear

Board size climbs on its own: the first half of your rounds are 3 by 3 and the rest step up to 4 by 4. The reveal appears only after the last one. See the round list in the preview before you publish, because a 4 by 4 with division is a real sit-down puzzle.

Difficulty

Difficulty sets which operators appear and how many cells are left blank. Division always comes out even, so no fractions ever show up. Every board can be finished by reasoning alone, and the answer is always a single digit from 1 to 9.

Mistakes allowed

A mistake is counted when a finished equation does not balance. The count is kept in the player page, so treat it as pressure rather than a lock.

Reveal (shown after the last round)

Message (optional)

Reveal image URL (optional)

Reveal either final coordinates or a keyword Final coordinates

Keyword (for a geochecker)

Where can I host images for free?

Paste a direct https:// link to an image. Free image hosts that give a direct link include ImgBB, postimages.org, and Cloudinary. A geocaching.com image link works too. The link must start with https://.

I understand this cache is public, contains nothing sensitive or inappropriate, and I am responsible for its content. I also understand that caches which sit unused are removed automatically: one that is never played is deleted 30 days after it is created, and one with no plays for two years may be deleted.

Keep your cache in play to keep it live. Share the play link so people visit it; unused caches are cleaned up over time.

Live preview

A real board at the size and difficulty you picked, dealt by the same generator the server uses. Every finder gets their own freshly generated grid, so nobody plays this one.

Pick a round above to see the board it deals.