Source Lichess
White wins at least 1.2 more of every 100 games than it loses
how far wins run ahead of losses, 90% confident
At All Ratings, Latvian Gambit: Mason Countergambit keeps White's wins running +1.2% ahead of its losses at worst, 90% confident, from 239K Lichess games. This gambit is playable but marginal. Win rate, draw rate and loss rate come from games played December 2023 to November 2025.
| Rating | Edge at worst | White Win | Draw | White Loss | Games |
|---|---|---|---|---|---|
| 0-999 | +7.4% | 53.4% | 2.6% | 44.0% | 6.3K |
| 1000-1199 | +9.9% | 54.8% | 1.8% | 43.3% | 10K |
| 1200-1399 | +6.2% | 52.8% | 1.8% | 45.4% | 19K |
| 1400-1599 | +4.7% | 51.9% | 1.9% | 46.2% | 30K |
| 1600-1799 | +0.3% | 49.4% | 2.4% | 48.3% | 45K |
| 1800-1999 | −1.5% | 48.2% | 2.9% | 48.9% | 58K |
| 2000-2199 | −2.4% | 47.5% | 3.5% | 49.1% | 45K |
| 2200-2499 | −2.4% | 47.3% | 4.1% | 48.6% | 23K |
| 2500+ | −5.7% | 46.1% | 5.1% | 48.8% | 2.8K |
1800-1999 is where the games stop proving it. Below that, White comes out ahead; from there up, the evidence no longer shows it. Where the line sits changes with the clock, so set yours above and look again.
White wins 49.4% of Latvian Gambit: Mason Countergambit games, draws 2.8% and loses 47.8%. That rests on 239K games from Lichess.
1000-1199. There White wins at least 9.9 more of every 100 games than it loses (90% confident), its highest Edge at worst.
Rapid. For White, the Edge at worst — how far wins run ahead of losses, 90% confident — is +2.6% in Blitz (98K games) and +7.9% in Rapid (17K games).
Yes. The first rating where the games do not show White coming out ahead is 1400-1599 in Bullet, 1800-1999 in Blitz and 1800-1999 in Classical. In Rapid, White comes out ahead at every rating we can see.
The Latvian Gambit: Mason Countergambit is extremely sharp: 2.8% of its games are drawn, so 97.2% end with a winner.
Play it below 1800-1999. From there up, the games no longer show it paying. Where the line sits changes with the clock, so set yours above and look again.
As Black, take the material, then develop fast, castle early, and trade pieces. Give the material back when doing so kills the attack. At 1800-1999 and above, the games no longer show White coming out ahead with it; below that, they do.
This rests on 239K games from Lichess. Every figure carries the range it is in, 90% confident, and the table above shows how many games sit behind each rating and each clock — the fewer there are, the wider that range.