How it works

Simple to learn, brutal to master. First to 100 points takes the match.

CATS

Grow it

Start from a 3-letter word. Add a letter to either end to make a longer one — cat → cats.

CART

Or spin a dial

Change one letter in place to a new one — cart → care. Every result must be a real word. No repeats.

?···

Outlast them

No move on your turn? That's a jam — and three jams lose the duel. Corner your rival while the score climbs to 100.

A real Letterex duel at 30 points each: the word CARES locked on the brass cryptex rail, The Locksmith perched above it, and the scored chain of words played so far listed below. — The real thing — mid-duel at 30–30.

One duel. Everyone. Every day.

The Daily Duel & Zen Mode

Every day, everyone gets the same duel: one word, one difficulty, The Locksmith across the table, first to 100. When it's over you get a clean result card — send it to the group chat and see who had the better day. No account, no login.

Rather play alone? Zen Mode is just you, one cylinder, and a single chain of words you keep alive for as long as the dictionary lets you. No clock. No opponent. Just you and the words.

Try today's Duel

A Letterex result card: Alex wins, first to 100 — final score 100 to 90, 29 words played, with the full chain of words listed and The Locksmith conceding with a quote. — Your results card after defeating The Locksmith.

Letterex Complete (App only)

One purchase opens the whole mechanism, forever.

$1.99 · once · no subscriptions

The Locksmith, all three strengths

Apprenticefree
Journeymanunlocked
Mastermindunlocked

Your Stats, every door open

Lifetime Ledgerunlocked
Chain Relics & Letter Countunlocked
Duel Archive — play any past Daily Duel againunlocked

💡 Three hints every duel

The unlock is for the app only. The browser is already unlocked!Play it free →

Frequently asked

Quick answers about how Letterex plays, and what it does — and doesn't — collect.

Is Letterex a two-player word game?

Yes. Letterex is built around head-to-head play — pass your phone back and forth in local pass-and-play duels, or let The Locksmith AI stand in when you're playing solo.

Can we play pass-and-play on one phone?

That's the whole idea. Hand the phone to your opponent each turn — no second device, no Wi-Fi, and no account required.

Do I need an account or an internet connection?

No. Letterex works fully offline, with no sign-in, no accounts, and no tracking of any kind — in your browser and in the apps.

Is the free web version the full game?

Yes. letterex.app/play is the complete game, free in your browser, offline included. The $1.99 Letterex Complete unlock applies to the mobile apps, where free play starts with the Apprentice difficulty and one hint per duel.