Bridge Scoring Calculator

How duplicate bridge scoring works

Every made contract starts with trick points, and only the odd tricks — the ones beyond the book of six — earn them. Minor-suit contracts (clubs and diamonds) score 20 per odd trick, major-suit contracts (hearts and spades) score 30, and notrump scores 40 for the first odd trick and 30 for each one after. Doubling multiplies trick points by two, and redoubling by four.

Trick points decide the most important threshold in the game: 100 or more earns the game bonus — 300 when not vulnerable, 500 when vulnerable — while anything less takes a flat 50 partscore bonus instead. That single rule explains the shape of nearly every auction. 3NT (40 + 30 + 30 = 100), 4 hearts or 4 spades (4 × 30 = 120), and 5 clubs or 5 diamonds (5 × 20 = 100) are the cheapest game contracts in each strain, which is why experienced bidders stretch toward exactly those levels and rarely stop in 4NT or 5 hearts by choice.

Slams stack on top. Bidding and making a level-six contract adds a small slam bonus of 500 (or 750 vulnerable); a level-seven grand slam adds 1000 (or 1500 vulnerable). Made doubled contracts also collect 50 "for the insult" — 100 if redoubled — plus inflated overtrick values: 100 per overtrick doubled when not vulnerable, 200 vulnerable, and twice that redoubled.

Undertricks: what going down costs

When declarer falls short, the defenders score instead. Undoubled undertricks are simple: 50 each when not vulnerable, 100 each when vulnerable. Doubled penalties escalate — not vulnerable they run 100 for the first undertrick, 200 for the second and third, and 300 from the fourth on; vulnerable they run 200 for the first and 300 for each after. Redoubled penalties double the doubled numbers.

The escalation is the strategic point. Down three doubled and vulnerable costs 800, which is worse than letting opponents make a non-vulnerable game. That arithmetic drives the classic sacrifice decision: a cheap set can be a good result if the alternative was conceding a game or slam bonus. Try a few of those comparisons in the calculator — it is the fastest way to build intuition for when a sacrifice pays.

Duplicate, rubber, and the scoring at this table

The calculator uses standard duplicate scoring, the system used in clubs, tournaments, and nearly all online bridge, where each deal is scored independently and bonuses are baked into the single number. Rubber bridge — the traditional home game — splits scores above and below the line and awards game and rubber bonuses across deals instead; the trick-point values are the same, so the calculator's trick-score line still applies, but the bonus structure differs.

The playable game on this site sits deliberately on the simpler end: it uses streamlined hand scoring without doubles or vulnerability, totaled across a four-deal Chicago match, so you can concentrate on the auction and card play. Think of this page as the bridge to real-table scoring — bid and play a hand at home on the practice table, then plug the same contract into the calculator to see what it would have been worth at a duplicate club. The Bridge rules explain how contracts and tricks work, and the bidding guide covers how to reach the game and slam contracts these bonuses reward.