I assumed it was one game in four languages

GlyphDuel runs in English, French, Spanish and German. When I built it I treated the language as a setting, like a skin. Swap the dictionary, swap the keyboard layout, done.

That was wrong in two separate ways, and the second one took a spreadsheet to see.

France didn't copy Wordle. It already had its own.

This is the part English speakers usually miss. When Wordle went viral in early 2022, France didn't need converting. It had been watching the same puzzle on television for decades.

Motus ran for years on France 2: guess the word, first letter given, coloured squares. On 8 January 2022 a developer called Jonathan Magano spent a few hours coding the television rules into a web page and published it as SUTOM, which is simply MOTUS spelled backwards.

It is now the default French word game, and its rules differ from Wordle in two ways that matter:

Longer words and a free letter. Most people assume those cancel out, with the longer words making it harder overall. I measured both. They don't cancel out. They stack, in the same direction.

What a free first letter is actually worth

Here's the calculation, run on the French dictionary because that's where the rule lives.

There are 2,631 six-letter French words in it. Reveal the initial and every word starting with a different letter vanishes.

How many survive? It depends which letter, so it has to be weighted: a random word is far likelier to start with C than with W. Weighted across all of them, 171 candidates remain out of 2,631.

93.5% of the dictionary, gone before you type anything.

In information terms the revealed letter carries 4.12 bits. A strong five-letter opener earns you roughly 4.5. So:

The letters are wildly unequal, too. In six-letter French, C opens 275 words and P opens 256, while W opens exactly one and Y opens two. Draw a W word and you have essentially already won.

Longer words are easier, not harder

This is the half that surprises everyone. I gave it a whole article; here it is in one line.

A word is hard when many other words resemble it to within one letter. Short words are crammed into too small a space and pile up on each other. Long words have room to be unique.

Going from five letters to six cuts the risk by a factor of six. The seven, eight and nine-letter words Sutom serves are more isolated still.

So both of Sutom's distinguishing rules make it easier. The wider grid is an optical illusion: more boxes to fill, but each box tells you more, and the answer has far fewer lookalikes waiting at the end.

The language itself changes the difficulty

That was the rules. The second difference is the language, and it is not a matter of how well you speak it.

Counting one-letter neighbours across all four dictionaries gives the share of words that deduction cannot rescue you from:

Spanish is the hardest by a distance, because it leans so heavily on vowels that its words collide constantly. German is the easiest at short lengths for the mirror-image reason. The full explanation is here.

Which language should a learner start with?

Here's the tension, and I find it genuinely funny.

German is the easiest language to guess in and the hardest to learn. Everything that makes it painful for a student (long words, heavy morphology, few vowels) is exactly what makes its words distinctive on a grid. If you want a gentle entry into playing in a foreign language, German is it, whatever your teacher told you.

Spanish is among the friendliest languages to learn and the most brutal to guess in. You will read the answer and know every word in the cluster. That won't help you pick the right one.

French sits in the middle on the grid, and if you play Sutom rather than a Wordle clone, the free first letter tips it further in your favour.

My practical advice for a learner: play at five or six letters, never four. Four-letter mode is where the traps live, and guessing between twelve near-identical short words in a language you're still learning is discouraging rather than instructive.

Where to play

Sutom is the canonical French one. Motus rules, one word a day, free, no account, with an unlimited practice mode. If you want the authentic French experience, that's it. Tusmo offers the same mechanics with a more polished interface and extra modes including duels. Le Mot is a plainer take, closer to original Wordle.

GlyphDuel, which I build, does two things those don't: real-time multiplayer in a private room, everyone on their own grid with points to whoever solves first; and four languages with three word lengths in one place, which is the practical reason it exists for learners. There's a daily word and an unlimited solo mode too.

Where the numbers come from

The French validation dictionary in GlyphDuel: 1,808 five-letter words, 2,631 six-letter. The first-letter value is the Shannon entropy of the initial-letter distribution, plus the average surviving field weighted by each initial's probability. Trap words are those with five or more neighbours at Hamming distance 1.

Two limits worth stating. GlyphDuel's dictionary stops at six letters, so I'm measuring the bottom of Sutom's range; at eight or nine letters the gap would favour Sutom even more. And dictionaries differ between games, so these are structural tendencies rather than a ranking of any particular day's puzzle.

Sutom's rules and history come from its Wikipedia entry and official site.

One last thought

We judge a word puzzle by how big the grid looks. Nine boxes feel worse than five. It's the wrong instinct entirely: difficulty lives in how many words resemble the answer, and in how much each clue actually buys you.

France quietly built the easier game and nobody noticed, because it looks like the harder one.

If you want the mechanics: the trap words, why short words are harder, and which language is hardest.