How We Design WordFren's Daily Word Puzzle

Every WordFren Daily Puzzle starts from the calendar date. The date becomes a seed, the seed picks four target words and plants them on an 8x8 grid, and the rest of the grid is filled with letters weighted toward everyday English. Each candidate board has to pass a quality check before anyone sees it. You then get 90 seconds to trace words through touching letters, with combos, cascades and a shared leaderboard deciding how the day went.

This post walks through each of those decisions and the reasoning behind them, using the actual rules in the app.

Goal: a puzzle that is fair, fast and worth sharing

We started with three constraints.

• Fair. Everyone plays the same board, so a score means the same thing for every player that day.
• Fast. A round has to fit into a coffee break. That meant a hard time limit rather than an open-ended puzzle.
• Never dead. A random grid of letters can easily contain almost no words. A daily puzzle cannot afford a bad day, because everyone gets the same bad board.

Most of the engineering described below exists to satisfy the third rule without breaking the first.

Step 1: one seed per day

The board's random number generator is seeded from a string built from today's date in UTC. Every device that runs the generator with that seed makes the same choices in the same order, so every player gets an identical starting grid.

Two small details matter here:

• UTC, not local time. Everyone switches to the new board at the same moment, midnight UTC, so the puzzle number matches worldwide. Puzzle numbers count up from 1 January 2025, which was Daily #1.
• Sorted word lists. Swift sets have no guaranteed order, and a different order would mean a different pick from the same seed. The word bank is sorted before selection so the pick is identical on every device.

Step 2: pick target words first

A lot of letter-grid games generate letters and hope words appear. We do it the other way around. For the Daily Puzzle, the generator picks four target words from the common tier of WordFren's curated gameplay list, and each must be at least four letters long. The pick is weighted, so some words are more likely than others, but the seed decides which ones come up.

Why common words? The Daily Puzzle is the one game everyone plays, including people who opened the app for the first time five minutes ago. Guaranteeing a few familiar words gives everyone a foothold. Harder, rarer words still show up in the leftover letters, and they score more when they do.

Step 3: plant the words in the grid

Each target word is placed in one of four directions: left to right, top to bottom, or along either downward diagonal. The generator tries up to fifty random start positions for each word. A placement is allowed if every cell is either empty or already holds the same letter, so target words can cross and share tiles, the way crossword entries do.

If a word will not fit after fifty tries, the generator makes a second, looser attempt. If that also fails, the word is skipped rather than forcing an ugly board.

Step 4: fill the gaps with weighted letters

The remaining cells are filled one at a time using letter weights based on how common each letter is. For the Daily Puzzle, the generator uses its gentlest weight table:

The zero weights mean fill letters never include J, Q, X or Z. Those letters can still appear on a Daily board, but only when a planted target word contains them. That keeps the board from filling up with tiles almost nobody can use in 90 seconds.

Themed Word Worlds boards use the same generator but plant words from that world's list, and later worlds switch to heavier weight tables with more room for Q, X and Z.

Step 5: check the distribution

After filling, the board is checked against hard rules:

• At least 30 percent of tiles must be vowels.
• No row may contain more than one of J, Q, X or Z, and the whole board may contain no more than three.
• No row or column may contain a run of more than four consonants in a row.

If any rule fails, the fill letters are wiped (the planted words stay) and the gaps are refilled, up to fifty times.

Step 6: grade the board

Passing the distribution rules only means the board is not obviously broken. Next, the generator grades it by scanning every row and column for real words and measuring:

• how many distinct valid words appear,
• how many are short and easy (three or four letters),
• whether words overlap and share tiles,
• whether any single row or column holds two or more words, which makes cascades more likely,
• the vowel ratio, the count of rare letters, and the longest consonant run.

This grading counts only straight-line words in rows and columns. Players can trace words through any chain of touching tiles, including diagonals and bends, so the real number of findable words is always higher. The grade is a conservative floor.

The generator tries up to fifty seeds derived from the day's seed and keeps the first board that grades C or better. If none does, a rescue step builds a board around a short list of friendly anchor words such as STAR, RAIN, NOTE and LIGHT, then grades that. The result is that no player should ever open a Daily Puzzle with nothing to find.

Step 7: how you play the board

You drag a finger through letters that touch in any of eight directions: across, down or diagonally. A tile can be used once per word. Tapping a letter without dragging switches to tap-to-select, where you tap neighbouring letters one by one and tap the last one again to submit, which also works with VoiceOver.

When you submit a valid word:

• its tiles clear,
• tiles above fall down to fill the gaps,
• new letters drop in from the top.

Those new letters are also seeded. The same sequence of moves on the same day produces the same board for anyone, so the leaderboard compares play on equal terms.

Step 8: scoring that rewards both speed and quality

We wanted both a fast player and a thoughtful player to have a path to a good score. The rules:

• Base score: word length squared, times 10. A three-letter word is 90, a five-letter word 250, a seven-letter word 490.
• Rare-letter bonus: plus 20 for every Q, Z, X, J or K in the word.
• Combo multiplier: find your next word within three seconds and the combo level rises, up to level 5. Levels 1 to 5 multiply by ×1, ×1.5, ×2, ×2.5 and ×3. Pause longer than three seconds and it resets.
• Repeat penalty: the same word scores 100 percent the first time, 50 percent the second, 25 percent the third and 10 percent after that.
• Rarity bonus: words WordFren classifies as uncommon, rare, epic or legendary add 10, 25, 50 or 100 points.
• Board clear: emptying the entire grid adds 500 points.
• Safety cap: a single move can add at most 15,000 points, so one lucky chain cannot swamp a whole round.

The ×3 ceiling is deliberate: it stops raw speed from dominating, so a six-letter word stays competitive with a burst of three-letter ones.

Cascades

After the refill, the game scans rows and columns for any valid word. If it finds one, that word clears automatically as a cascade, more tiles fall, and the scan runs again. Each move allows up to two cascades, which keeps turns quick and prevents the board from playing itself.

Cascade words score at a higher combo level than the word that triggered them, plus a flat bonus of 50 for the first cascade and 75 for the second.

A worked example

• You open with STONE: 5 letters, 5 × 5 × 10 = 250, at ×1. 250 points.
• Two seconds later you trace NOTE: 4 × 4 × 10 = 160, combo level 2, ×1.5. 240 points.
• The refill lines up TEA in a row, which clears as a cascade at combo level 3 (×2): 90 × 2 = 180, plus the 50-point cascade bonus. 230 points.

One move after an opening word earned 470 points, and your combo is already climbing for the next word.

Step 9: 90 seconds, a leaderboard and a share card

Rounds last 90 seconds. That is long enough to find a dozen words and short enough that the combo decision (keep moving, or stop to look for something longer?) feels tense.

For the leaderboard, raw scores are converted to a 0 to 10,000 scale so rankings stay comparable from day to day. You still see your actual points everywhere else in the app.

The share card opens with an emoji grid, a square for each word you formed, tinted by word length, followed by your score, word count and longest word length. Friends can see how you played without seeing which words were on the board. If you found a rare word, the card names it as a small brag.

Why every word comes with a definition

Words you find can open a discovery card with a definition, pronunciation, example sentence and synonyms. During the round, the game also notices near-misses: if slotting in one adjacent letter would have made a longer word, a quick "so close" message tells you what was hiding nearby. The idea is that the puzzle should leave you with a word or two you did not know that morning. If you want more of that, the vocabulary games page lists other ways to learn words through play, and the word of the day gives you one new word to carry into tomorrow's puzzle.

Tips from the design side

Knowing how the board is built suggests a few strategies:

• Look for the planted words first. Four real words of four letters or more are sitting in straight lines, including diagonals.
• Watch rows and columns after each clear. Cascades only happen along straight lines, so the refill above your word is where the free points appear.
• Keep moving. Three seconds is a short window. Two quick short words usually beat one slow long word early in a round.
• Do not replay a word. The repeat penalty halves your score the second time.

For more on tracing touching letters efficiently, our Boggle strategy guide covers vowel-first scanning and suffix checks that transfer directly to the Daily Puzzle.