Spades is a trick-taking game built on a promise. Before any card hits the felt, all four seats announce how many tricks they intend to win, and the two bids on each side of the table merge into a single partnership contract. From that moment the hand is not about winning as much as possible — it is about delivering exactly what was promised. Land the contract and every bid trick pays 10 points; miss it and those same tricks are subtracted instead.
At this table you sit South with North as your AI partner, facing the West-East partnership. Bidding runs one round with no second chances, nil is always on the menu, spades are permanent trump, and a spade cannot be led until one has been played to another suit — unless a hand holds nothing else. Difficulty is selectable, no signup is required, and your match statistics persist between visits.
The scoring carries real depth. Overtricks look harmless at one point each, but each one also banks a bag, and the tenth bag fines the partnership 100 points on the spot. A nil bidder chases a 100-point bonus that inverts into a 100-point penalty the instant a single trick sticks to them. Hand results accumulate across deals, and the match is decided only when a side climbs past 500 — or sinks through the −200 floor and loses outright.
That structure creates the strategic texture Spades players love. Sometimes the right play is refusing a trick you could easily win, because your contract is already made and the bag would inch you toward the penalty. Sometimes it is deliberately feeding overtricks to opponents sitting at eight bags. And covering a partner's nil turns half your hand into bodyguard duty.
If the arithmetic is the part you are rusty on, the rules page walks through bidding, nil, bags, and worked hand scores, while the strategy guide covers bid counting and nil protection. This site also includes a Spades score calculator that applies contract, nil, and sandbag math for you — useful for house games — and the variations page explains jokers, Suicide, Whiz, and Mirror if your table bids differently.