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Card games table

Playcards

Mau-Mau, Schlafmütze, Blackjack, Skat and Doppelkopf vs the computer, at home or online.

Launch Playcards → Tutorials

Playcards is a card table for five classic games: Mau-Mau, the quartet race Schlafmütze, Blackjack with play money, Skat by the International Skat Order and Doppelkopf by the DDV tournament rules. Play against computer players in three levels, pass one device around with a privacy screen, or invite friends to an online table with a six-character code. Every game has its own rules page, tutorial, house rules and statistics.

Free · runs in your browser · no sign-up · Version 1.0.0

Skat table in Playcards with German-suited cards: a trick in the middle, the declarer’s Hearts game and the player’s sorted hand

Screenshots

Features

  • Five games, one table

    Mau-Mau, Schlafmütze, Blackjack, Skat and Doppelkopf, each with its own rules page, house rules and tutorial.

  • Computer players in three levels

    Easy players make human mistakes; the strongest Skat and Doppelkopf players look ahead by dealing the unseen cards at random — without ever seeing your hand.

  • Pass the device

    Play with friends on one computer or tablet: a privacy screen hides every hand until the next player is ready.

  • Online tables with an invitation code

    Open a table, send the link or the six-character code, and friends join from their own browser. Empty seats can be filled with computer players.

  • Skat by the ISkO

    Bidding with every valid bid value, Hand, Schneider and Schwarz announcements, Ouvert, Grand and Null, matadors, overbid games and Ramsch as a house rule.

  • Doppelkopf by the DDV rules

    Re and Kontra with the right announcement times, Hochzeit, Queen, Jack, suit and Fleischlos solos, fox, Karlchen and Doppelkopf, with or without nines.

  • Blackjack with real casino rules

    Shoe with a cut card, double, split, insurance and surrender, dealer on soft 17 or not — and a hint button with basic strategy computed for your table. Play money only.

  • Mau-Mau with house rules

    Sevens draw two (stackable), eights skip, Jacks wish a suit; say “Mau” in time. Switch on reversing nines, Ace again or Jack on Jack.

  • Schlafmütze, the quartet race

    Pass cards at the same time and grab a token when someone shows four of a kind. Relaxed computer reactions give everyone time — by keyboard too.

  • French or German cards

    Card faces drawn for this app, Acorns, Leaves, Hearts and Bells for Skat, Doppelkopf and Mau-Mau, and suit symbols that do not rely on colour.

  • Play by keyboard and screen reader

    Every card has a name, arrow keys choose a card and Enter plays it, and every move is announced. Reduced motion is respected.

  • Autosave and statistics

    Local games are saved in your browser and continue where you left off; wins, rounds and points are counted per game. Bundlekeep backs them up.

  • Three tools for AI agents

    Skat game values, Doppelkopf scores and Blackjack strategy as tools with a JSON API and MCP — the same engine as the app.

Templates

Start from a ready-made project and change it to fit.

Built-in tools

Playcards uses these tools. Each one also has its own page and works on its own, in the browser, through the JSON API and through MCP.

For AI agents

Playcards runs on a deterministic engine. The same functions are available as tools with a JSON API and MCP, so scripts and AI agents get exactly the results the app shows.

  • Skat Game Value Calculator – Skat game value from contract, matadors, Hand, Schneider, Schwarz and Ouvert — with overbid check.
    Tool page · POST https://playcards.usefulweb.site/api/v1/tools/playcards-skat-game-value/calculate · MCP playcards_skat_game_value
  • Doppelkopf Score Calculator – Doppelkopf game points from card points, announcements and special points (DDV rules).
    Tool page · POST https://playcards.usefulweb.site/api/v1/tools/playcards-doppelkopf-score/calculate · MCP playcards_doppelkopf_score
  • Blackjack Basic Strategy Calculator – Blackjack basic strategy chart and expected values computed for your table rules.
    Tool page · POST https://playcards.usefulweb.site/api/v1/tools/playcards-blackjack-strategy/calculate · MCP playcards_blackjack_strategy

Build a project through the API, then open it in the app with a link to https://playcards.usefulweb.site/app#project=<base64url JSON>.

Import & export

Import

  • Playcards table (.playcards.json)
  • Share link with the table set-up (#project=)

Export

  • Playcards table (.playcards.json) with the running game
  • Share link with the table set-up (no cards)
  • Score sheet as CSV

Keyboard shortcuts

Keyboard shortcuts in Playcards
KeysAction
← / →Choose a card in your hand
EnterPlay the chosen card
SpaceSchlafmütze: grab a token
DMau-Mau: draw a card
H / SBlackjack: hit or stand
NNext round when the round is over
RRead the table aloud (status for screen readers)
?Show keyboard shortcuts

Frequently asked questions

Can the computer players see my cards?

No. A computer player gets exactly what a person in its seat would see: its own hand, the cards on the table and the history. The strongest level deals the cards it has not seen at random many times and plays them out to choose a card.

How does playing online work?

Choose Online, pick a game and open a table. You get a link and a six-character code to send to your friends; they open the link or type the code on the Playcards page and choose a name. Empty seats can be computer players. The server deals and checks every move and sends each player only their own cards.

What is stored about online tables?

Only what the game needs, in the server’s memory: the table code, the display names you chose, the cards and moves, and a hash of each seat’s secret key. A table disappears after two hours without moves or when the host closes it. See the privacy policy.

Which Skat rules are used?

The International Skat Order (ISkO): bidding with all valid values, Hand, Schneider and Schwarz announcements, Ouvert, matadors, overbid games and the score sheet with lost games counting double. Ramsch and Seeger-Fabian scoring are optional house rules.

Which Doppelkopf rules are used?

The tournament rules of the Deutscher Doppelkopf-Verband (DDV): 48 cards, first Dulle wins, Hochzeit, solos, announcements with their deadlines and the special points. House rules: without nines, second Dulle beats the first, solos and special points off.

Is this gambling?

No. Blackjack uses play chips that have no value and cannot be bought or paid out. It is for learning the rules and basic strategy.

How do we play on one device?

Choose “Pass the device” and enter the names. Before each turn a privacy screen asks the next player to take the device and press Show my cards, so nobody sees another hand.

Are my games saved?

Games against the computer and on one device are saved in this browser automatically, with statistics per game. Save a table file to keep it elsewhere; Bundlekeep can back up all Playcards tables.

Limitations

What Playcards does not do (yet):

  • Online tables live in the server’s memory: a server restart ends running tables, and a table is removed after two hours without moves.
  • Doppelkopf has no compulsory solo (Pflichtsolo), no Armut/poverty and no Schweinchen; the soloist does not lead the first trick (Lustsolo rule).
  • Skat is played by three at one table; there is no four-player table with a sitting-out dealer, and Kontra/Re in Skat is not offered.
  • Schlafmütze on one device needs every player to share the keyboard (each seat has its own grab key).
  • Blackjack follows the US hole-card game with dealer peek; there is no European no-hole-card rule and no side bets.
  • Computer players are strong amateurs, not tournament software; they do not use bidding conventions or Doppelkopf signalling systems.
  • There is no chat; talk to your friends by your own means.

Tutorials

Learn Playcards step by step.

  1. Mau-Mau rules and house rulesPlay Mau-Mau against the computer, learn what sevens, eights and Jacks do, and switch on the house rules your family plays with.Beginner 6 min
  2. Schlafmütze: the quartet racePass cards at the same time, collect four of a kind and grab a token before the others — with relaxed or fast computer players and a keyboard alternative.Beginner 5 min
  3. Blackjack with a strategy hintPlay casino Blackjack for play chips, use double, split, insurance and surrender, and let the basic-strategy hint show the best move for the chosen rules.Beginner 6 min
  4. Skat: bidding, games and game valuesPlay Skat by the International Skat Order against two computer players — bidding, picking up the Skat, choosing a game and reading the game value.Intermediate 9 min
  5. Doppelkopf: parties, announcements and scoringPlay Doppelkopf by the German Doppelkopf Association's tournament rules — secret parties, reservations and solos, Re and Kontra, special points and the score.Intermediate 9 min
  6. Playing with friends on one device or onlinePass one device around with a privacy screen, or open an online table, send the invitation link with its six-character code and play with friends far away.Beginner 6 min
  7. Saved tables, statistics and AI toolsSave and reopen tables, share a set-up, read your statistics and score sheets, and use the Skat, Doppelkopf and Blackjack tools from AI agents through the JSON API and MCP.Intermediate 5 min

Ready to try it?

Launch Playcards →

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