How do I play this Mastermind-style game online?

This is an original color-code game with no commercial puzzle affiliation. Fill each position using the palette, then choose Submit guess. Use the exact and misplaced counts to revise the next guess. The core game is free in a current browser on a phone, tablet or computer, with no account or installation.

Can I play with a friend?

Yes, by exchanging a challenge after you solve a first-attempt code. Your friend opens the link, plays the same seeded code independently and compares the guess count. This is asynchronous play; there is no live two-player room or human code-setting mode.

Can I play a Mastermind-style number game online?

Choose Numbers under Code symbols, then start a code. Fill four to six positions with digits 1 through the selected number count, from six to eight. Exact and misplaced feedback uses the same rules as color play. The palette, entry row, history, revealed answer and session TXT use digits. Saving, resuming and friend challenge links retain number mode; result cards label the number settings.

What do exact and misplaced mean?

Exact counts the correct symbol in the correct position. Those matches are removed first. Misplaced then counts symbols present elsewhere in the remaining secret. Every secret position counts at most once. The feedback gives totals and does not identify which guess positions matched.

Can colors repeat in the hidden code?

Choose repeats allowed or not allowed before starting a new code. With repeats off, both the hidden code and each guess must use distinct colors. There are four to six positions and six to eight available colors.

How does repeated-color feedback work?

For secret AABC and guess AAAA, feedback is two exact and zero misplaced. For secret AABC and guess ABCA, feedback is one exact and three misplaced. A guessed color cannot be credited more times than it appears in the remaining secret.

How do I play without relying on color?

Each color has a letter and a visible name. Select a position, then choose a palette button. While focused in the board, A–H or 1–8 enters colors, arrow keys change position and Backspace clears a position. Enter on the board submits a guess; all controls are also reachable with Tab. In Numbers mode, use digits 1 through the available number count; letters do not enter numbers.

Can I save and resume a game?

Save current game stores one snapshot on this browser. It retains the seed, symbol mode, rules and guesses; a new game does not overwrite it automatically. Resume saved game restores the same code and feedback as practice. Clear saved game removes the stored snapshot without changing the active game.

How do friend challenges work?

Solve a first-attempt game, then copy or share its link or download a result card. The link carries the seed, encoded symbol mode, rule settings and claimed guess count. A recipient plays the same code and can share their completed result. Scores are self-reported; seeds are public and this is not an anti-cheat competition.

What ends a game or disables result sharing?

A correct guess wins, the twelfth incorrect guess ends the game, and Reveal answer ends play immediately. Revealed, restarted and resumed games are practice and cannot create a scored challenge. Reusing the same seed and rule settings, even after switching between colors and numbers, during this page session also starts practice.

Color Codebreaker

Use each guess to uncover a hidden sequence of colors or numbers. Choose the symbols, code length and repeat rule, then solve within twelve guesses and share the same puzzle without an account.

Choose the puzzle

Code symbols

Code lengthAvailable colorsRepeated colors

Puzzle seed

Settings apply when you start a code. Starting replaces the active game; save it first if needed. Switching between colors and numbers leaves the same hidden code. Reusing the same seed and rule settings in this session is practice. A seed is reproducible and public, so these are friendly, self-reported challenges.

Crack the hidden code

Active puzzle: 4 positions · 6 colors · repeats allowed · seed 42.

Guesses used0

Guesses left12

Best exact count0/4

Select a position, then a color. The active position advances after each choice. Color letters and names make every clue readable without relying on color.

Keyboard while focused in the board: A–H or 1–8 enters a color; left/right chooses a position; Backspace clears it. Enter on the board submits. Tab reaches every control. You have 12 guesses. Previous choices stay in the entry row for editing after a guess.

Guess history

Exact: correct color in the correct position. Misplaced: correct color in another position, after exact matches are removed. Each secret position counts once. These are counts, not clues attached to particular positions.

Your first submitted guess will appear here.

Keep this game

Save explicitly to keep one game on this browser. Starting a new code does not overwrite it. Loading a saved game preserves its seed, symbol mode, rules and guess history but marks it as practice. There is no account or automatic sync.

Preparing a code…

Common questions

How do I play this Mastermind-style game online?: This is an original color-code game with no commercial puzzle affiliation. Fill each position using the palette, then choose Submit guess. Use the exact and misplaced counts to revise the next guess. The core game is free in a current browser on a phone, tablet or computer, with no account or installation.
Can I play with a friend?: Yes, by exchanging a challenge after you solve a first-attempt code. Your friend opens the link, plays the same seeded code independently and compares the guess count. This is asynchronous play; there is no live two-player room or human code-setting mode.
Can I play a Mastermind-style number game online?: Choose Numbers under Code symbols, then start a code. Fill four to six positions with digits 1 through the selected number count, from six to eight. Exact and misplaced feedback uses the same rules as color play. The palette, entry row, history, revealed answer and session TXT use digits. Saving, resuming and friend challenge links retain number mode; result cards label the number settings.
What do exact and misplaced mean?: Exact counts the correct symbol in the correct position. Those matches are removed first. Misplaced then counts symbols present elsewhere in the remaining secret. Every secret position counts at most once. The feedback gives totals and does not identify which guess positions matched.
Can colors repeat in the hidden code?: Choose repeats allowed or not allowed before starting a new code. With repeats off, both the hidden code and each guess must use distinct colors. There are four to six positions and six to eight available colors.
How does repeated-color feedback work?: For secret AABC and guess AAAA, feedback is two exact and zero misplaced. For secret AABC and guess ABCA, feedback is one exact and three misplaced. A guessed color cannot be credited more times than it appears in the remaining secret.
How do I play without relying on color?: Each color has a letter and a visible name. Select a position, then choose a palette button. While focused in the board, A–H or 1–8 enters colors, arrow keys change position and Backspace clears a position. Enter on the board submits a guess; all controls are also reachable with Tab. In Numbers mode, use digits 1 through the available number count; letters do not enter numbers.
Can I save and resume a game?: Save current game stores one snapshot on this browser. It retains the seed, symbol mode, rules and guesses; a new game does not overwrite it automatically. Resume saved game restores the same code and feedback as practice. Clear saved game removes the stored snapshot without changing the active game.
How do friend challenges work?: Solve a first-attempt game, then copy or share its link or download a result card. The link carries the seed, encoded symbol mode, rule settings and claimed guess count. A recipient plays the same code and can share their completed result. Scores are self-reported; seeds are public and this is not an anti-cheat competition.
What ends a game or disables result sharing?: A correct guess wins, the twelfth incorrect guess ends the game, and Reveal answer ends play immediately. Revealed, restarted and resumed games are practice and cannot create a scored challenge. Reusing the same seed and rule settings, even after switching between colors and numbers, during this page session also starts practice.

Original recreational code-breaking rules. Each secret position is counted once in feedback. Shared scores are self-reported; revealed, restarted and resumed games are practice. No commercial puzzle affiliation.