Skip to content
TrueEloPlay what wins.
Score a position

Petrov's Defense: Classical Attack, Mason Variation

20K games from Lichess · Updated January 2026

1
2
3
4
5
6
7
h8
g
f
e
d
c
b
a
7...O-O
Analyze this line move by move

Black expected score · All ratings · All speeds

45.5%

40%55%
Floor44.9%

the worst score you would still get, 90% confident. At best 46.1%.

Measured over 20K games at this level and clock.

Tough Sellloses more often than it wins at this level

Black comes out behind here — there are better weapons in the list.

Outcomes for Black

Draw 7.1 · Score = win + ½ of the draws · 20K games

Rank among the families Black can choose here
not ranked — this is a variation, not a family
Games in this context
20K
Best context
49.0% at 1600-1799 Bullet
Worst context
41.8% at 2000-2199 Rapid
Average game length
38 moves
Games that end decisively
92.9%
Draws
7.1%

Best and worst are the strongest and weakest squares with at least 500 games behind them. The table further down shows every square, including thinner ones.

Where it holds · Black score by rating × clock

Green is clearly ahead for Black, grey is around even, red is behind. Tap a cell to measure there, and again to clear. It gets better as the rating rises: 35.5% at 0-999, 40.7% at 2500+.

RatingUBBulleBlitzRapidClass
0-999——
1000-1199——
1200-1399——
1400-1599
1600-1799
1800-1999
2000-2199
2200-2499—
2500+—

Expected score matrix by rating bracket and time control

  • 0-999 rating, Bullet: 28.3% expected score (10 games)
  • 0-999 rating, Blitz: 35.7% expected score (9 games)
  • 0-999 rating, Rapid: 42.4% expected score (5 games)
  • 1000-1199 rating, Bullet: 51.3% expected score (39 games)
  • 1000-1199 rating, Blitz: 36.5% expected score (28 games)
  • 1000-1199 rating, Rapid: 32.4% expected score (7 games)
  • 1200-1399 rating, Bullet: 49.6% expected score (118 games)
  • 1200-1399 rating, Blitz: 49.3% expected score (135 games)
  • 1200-1399 rating, Rapid: 48.4% expected score (29 games)
  • 1400-1599 rating, UltraBullet: 70.0% expected score (1 games)
  • 1400-1599 rating, Bullet: 44.7% expected score (421 games)
  • 1400-1599 rating, Blitz: 48.4% expected score (448 games)
  • 1400-1599 rating, Rapid: 39.4% expected score (97 games)
  • 1400-1599 rating, Classical: 27.0% expected score (5 games)
  • 1600-1799 rating, UltraBullet: 50.0% expected score (8 games)
  • 1600-1799 rating, Bullet: 49.0% expected score (762 games)
  • 1600-1799 rating, Blitz: 47.8% expected score (1,600 games)
  • 1600-1799 rating, Rapid: 46.1% expected score (345 games)
  • 1600-1799 rating, Classical: 30.3% expected score (34 games)
  • 1800-1999 rating, UltraBullet: 70.0% expected score (1 games)
  • 1800-1999 rating, Bullet: 46.9% expected score (1,269 games)
  • 1800-1999 rating, Blitz: 46.9% expected score (3,707 games)
  • 1800-1999 rating, Rapid: 46.5% expected score (772 games)
  • 1800-1999 rating, Classical: 42.5% expected score (98 games)
  • 2000-2199 rating, UltraBullet: 70.0% expected score (1 games)
  • 2000-2199 rating, Bullet: 44.7% expected score (1,311 games)
  • 2000-2199 rating, Blitz: 44.8% expected score (3,653 games)
  • 2000-2199 rating, Rapid: 41.8% expected score (1,034 games)
  • 2000-2199 rating, Classical: 37.0% expected score (56 games)
  • 2200-2499 rating, Bullet: 43.8% expected score (1,052 games)
  • 2200-2499 rating, Blitz: 44.1% expected score (1,804 games)
  • 2200-2499 rating, Rapid: 41.4% expected score (374 games)
  • 2200-2499 rating, Classical: 36.5% expected score (17 games)
  • 2500+ rating, Bullet: 42.1% expected score (250 games)
  • 2500+ rating, Blitz: 43.4% expected score (119 games)
  • 2500+ rating, Rapid: 35.1% expected score (22 games)
  • 2500+ rating, Classical: 42.3% expected score (5 games)

Related Openings

Parent
Petrov's Defense
49.1%
Variations (5)
Petrov's Defense: Three Knights Game
50.2%
Petrov's Defense: Italian Variation
50.9%
Petrov's Defense: Stafford Gambit
46.5%
Petrov's Defense: Modern Attack
51.5%
Petrov's Defense: Damiano Variation
58.6%
Analyze Petrov's Defense: Classical Attack, Mason Variation PositionsSee what each move is worth at your rating, move by move

Methodology

Across every rating and clock, the Petrov's Defense: Classical Attack, Mason Variation scores 45.5% for Black — we are 90% confident the real figure is between 44.9% and 46.1% — from 20K Lichess games. Win rate, draw rate and loss rate come from games played December 2023 to November 2025.

How the figures are made
Whose games these are
20K+ rated games played on Lichess (2023-12 to 2025-11). The games are Lichess’s and free for anyone to use. What is ours is the reading of them. Last rebuilt January 2026.
Which games we count
  • Rated games only — nothing casual.
  • Both players within 200 rating points of each other. A mismatch tells you about the gap, not about the opening.
  • At least 2 moves played.
  • A game is filed under White’s rating.
Why every number comes with a range
A number off a few hundred games is a guess. The same number off millions is a fact. The range is what tells them apart, and it is what the lists rank on — so an opening cannot reach the top on a lucky run of forty games. The more games behind a figure, the narrower its range.
How much we need before we say anything
An opening page needs 100 games. A gambit needs 50 games at a rating before we will say whether it pays there. The chaos and trap lists need 500 games overall and 250 games at one rating or clock.

Frequently Asked Questions

What is the Petrov's Defense: Classical Attack, Mason Variation win rate?

Playing the Petrov's Defense: Classical Attack, Mason Variation, Black wins 41.9%, draws 7.1% and loses 51.0%. Counting a draw as half a point, that is an Expected Score of 45.5%. It rests on 20K rated games from Lichess.

At what rating does the Petrov's Defense: Classical Attack, Mason Variation perform best?

The Petrov's Defense: Classical Attack, Mason Variation performs best for Black at 1600-1799, with an Expected Score of 47.7% (2.7K games) and the highest Floor of any rating with enough games to read.

Is the Petrov's Defense: Classical Attack, Mason Variation better in blitz or rapid?

For Black, the Petrov's Defense: Classical Attack, Mason Variation scores higher in Blitz: an Expected Score of 45.9% in Blitz (12K games) against 43.5% in Rapid (2.7K games).

How sharp is the Petrov's Defense: Classical Attack, Mason Variation?

The Petrov's Defense: Classical Attack, Mason Variation has a sharpness score of 92.9 (decisive), meaning 92.9% of games end decisively. Average game length is 38 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate at 1200-1399?

At 1200-1399, Black wins 47.4%, draws 3.7% and loses 48.9%. Counting a draw as half a point, that is an Expected Score of 49.3%. It rests on 282 Lichess games, which average 28 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate at 1400-1599?

At 1400-1599, Black wins 43.7%, draws 4.1% and loses 52.2%. Counting a draw as half a point, that is an Expected Score of 45.8%. It rests on 972 Lichess games, which average 31 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate at 1600-1799?

At 1600-1799, Black wins 45.1%, draws 5.2% and loses 49.7%. Counting a draw as half a point, that is an Expected Score of 47.7%. It rests on 2.7K Lichess games, which average 35 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate at 1800-1999?

At 1800-1999, Black wins 43.5%, draws 6.6% and loses 50.0%. Counting a draw as half a point, that is an Expected Score of 46.8%. It rests on 5.8K Lichess games, which average 37 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate at 2000-2199?

At 2000-2199, Black wins 40.4%, draws 7.7% and loses 51.9%. Counting a draw as half a point, that is an Expected Score of 44.3%. It rests on 6.1K Lichess games, which average 38 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate at 2200-2499?

At 2200-2499, Black wins 39.4%, draws 8.4% and loses 52.2%. Counting a draw as half a point, that is an Expected Score of 43.6%. It rests on 3.2K Lichess games, which average 41 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate at 2500+?

At 2500+, Black wins 32.3%, draws 19.2% and loses 48.4%. Counting a draw as half a point, that is an Expected Score of 42.0%. It rests on 396 Lichess games, which average 50 moves.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate in Bullet?

In Bullet, Black wins 42.8%, draws 5.6% and loses 51.6%. Counting a draw as half a point, that is an Expected Score of 45.6%. It rests on 5.2K Lichess games.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate in Blitz?

In Blitz, Black wins 42.3%, draws 7.2% and loses 50.5%. Counting a draw as half a point, that is an Expected Score of 45.9%. It rests on 12K Lichess games.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate in Rapid?

In Rapid, Black wins 39.1%, draws 8.8% and loses 52.1%. Counting a draw as half a point, that is an Expected Score of 43.5%. It rests on 2.7K Lichess games.

What is the Petrov's Defense: Classical Attack, Mason Variation win rate in Classical?

In Classical, Black wins 30.3%, draws 15.0% and loses 54.7%. Counting a draw as half a point, that is an Expected Score of 37.8%. It rests on 215 Lichess games.

Is the Petrov's Defense: Classical Attack, Mason Variation a good opening?

The Petrov's Defense: Classical Attack, Mason Variation is hard work for Black — it favours White. Across all ratings, Black wins 41.9% of its games and loses 51.0%. It performs best at 1600-1799. Your results depend on your rating, time control, and how well you know the typical plans.