Gambit ROI: Which Gambits Beat Their Engine Evaluation

Across 587 chess gambits with at least 50,000 Lichess games each, the Queen's Gambit Accepted: Normal Variation: Nc6 has the best practical-vs-engine gap — 69.0% for White against a Stockfish evaluation of only +0.87 — while the King's Gambit Declined: Falkbeer Countergambit: fxe5 is the worst, scoring just 14.5% for White despite Stockfish only rating the position -4.49.

A gambit's whole pitch is trading objective material or structure for practical chances. This study puts a number on that trade: an ROI score of White win % − 50 − (Stockfish eval in pawns × 100). A positive score means the gambit scores better for White in real games than its engine evaluation implies — the 'surprise value' that makes a gambit dangerous at the board even when it's not dangerous on a chess engine's assessment. A negative score means the opposite: the position is punished in practice roughly as hard as, or harder than, the engine already predicts.

The gambits with the highest surprise value

Five lines lead the ROI ranking: the Queen's Gambit Accepted: Normal Variation: Nc6 (+18.13), Queen's Gambit Accepted: Old Variation: b5 (+16.20), Center Game: von der Lasa Gambit: Bc5 (+14.94), and the Vienna Gambit: exf4 in both its Vienna Game and standalone forms (+13.54 and +13.53). These are lines where the practical result at 1200–1600 rating is meaningfully better for the gambiteer than a near-equal or only-slightly-worse engine score would suggest — the opponent's defensive task is harder than the evaluation implies.

The gambits that underperform their evaluation

At the other end, the King's Gambit Declined: Falkbeer Countergambit: fxe5 (-31.01), Bird Opening: Dutch Variation, Dudweiler Gambit (-27.90), and Queen's Pawn Game: Zurich Gambit (-18.84) score even worse in practice than their already-unfavorable Stockfish evaluations predict. These are gambits where the compensation genuinely fails to materialize against real opponents, not just against engines.

Gambit ROI ranking

GambitECOGamesWhite %Stockfish evalROI score
Queen's Gambit Accepted: Normal Variation: Nc6 D21 141,544 69.0% 0.87 +18.13
Queen's Gambit Accepted: Old Variation: b5 D20 1,577,652 67.1% 0.90 +16.20
Center Game: von der Lasa Gambit: Bc5 C21 269,517 66.1% 1.16 +14.94
Vienna Game: Vienna Gambit: exf4 C29 1,624,574 64.0% 0.46 +13.54
Vienna Gambit: exf4 C29 1,624,574 64.0% 0.47 +13.53
Vienna Game: Vienna Gambit: Bc5 C29 112,881 66.4% 3.16 +13.24
Vienna Gambit: Bc5 C29 112,881 66.4% 3.21 +13.19
Englund Gambit: Mosquito Gambit A40 99,339 65.3% 2.46 +12.84
Vienna Game: Vienna Gambit: Nc6 C29 522,910 63.1% 1.32 +11.78
Vienna Gambit, with Max Lange Defense: Nf6 C25 522,910 63.1% 1.37 +11.73
Vienna Gambit: Nc6 C29 522,910 63.1% 1.42 +11.68
Petrov's Defense: Stafford Gambit: Nxc6 C42 62,346 63.3% 1.66 +11.64
King's Pawn Game: Beyer Gambit: dxe5 C20 342,537 63.1% 1.55 +11.55
Bishop's Opening: Ponziani Gambit: d6 C24 169,950 62.4% 1.08 +11.32
Bishop's Opening: Ponziani Gambit: Nxe4 C24 378,816 62.1% 0.86 +11.24
Sicilian Defense: Polish Gambit B27 80,054 62.5% 1.62 +10.88
Queen's Gambit Accepted: Normal Variation: b5 D21 72,115 61.0% 0.50 +10.50
Bishop's Opening: Lewis Gambit C23 446,163 60.3% -0.09 +10.39
Queen's Gambit Declined: Albin Countergambit: dxe5 D08 144,701 61.3% 0.96 +10.34
Englund Gambit: Hartlaub-Charlick Gambit: Bf4 A40 98,236 61.6% 1.61 +9.99
Muzio Gambit C37 185,270 58.6% -1.21 +9.81
King's Gambit Accepted: King's Knight's Gambit: Nf6 C34 700,857 59.0% -0.37 +9.37
Scotch Gambit: Bc5 C44 2,082,675 59.0% 0.00 +9.00
Danish Gambit Accepted: Bc4 C21 3,257,409 58.3% -0.68 +8.98
Danish Gambit Accepted: Nf3 C21 207,318 58.1% -0.68 +8.78
King's Gambit Accepted: Bishop's Gambit: Nf6 C33 105,828 58.3% -0.38 +8.68
King's Gambit Accepted: Schallopp Defense: e5 C34 111,924 59.6% 0.97 +8.63
Center Game: von der Lasa Gambit: c5 C21 525,488 58.8% 0.37 +8.43
Queen's Gambit Declined: Baltic Defense, Queen Attack D06 75,167 59.0% 0.65 +8.35
Center Game: f6 C20 1,386,993 59.6% 1.54 +8.06

Download the data

Free to reuse under CC BY 4.0 — please link back to this page.

gambit-roi.csv gambit-roi.json

Methodology: win rates and game counts from the Lichess Opening Explorer (blitz + rapid games, 1200–1600 rating bands); position evaluations from Stockfish at depth 16. Snapshot: July 2026. See the full dataset methodology for details.