Chess Opening Theory/1. c4

English Opening
a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h
Position in Forsyth-Edwards Notation (FEN) rnbqkbnr/pppppppp/8/8/2P5/8/PP1PPPPP/RNBQKBNR b
Moves: 1. c4
ECO code: A10-A39
Parent: Starting position

1. c4 · English Opening

The English Opening, which starts with 1.c4, is the fourth most commonly played opening move in chess. By playing this move, White allows the queen to move freely and also discourages Black from responding with 1...d5. Additionally, White ensures that the c-pawn will not be blocked behind a knight on c3. The resulting positions often resemble those that arise from 1.d4 openings rather than 1.e4 openings, and the move d4 is frequently played later on.

While this opening is not as sharp as 1.e4 or 1.d4, it is still effective in controlling the d5 square and is highly flexible, allowing for easy transpositions into other openings.

Black's responses

• 1...Nf6 or 1...g6 are likely to transpose into an Indian Defence.
• 1...e5 is a "reversed" Sicilian Defence.
• 1...e6 will probably end up in a Queen's Gambit Declined. This is known as the Agincourt Defense. However, if White plays 2.d4 then Black plays 2...Nf6, it is a typical Indian game (1.d4 Nf6 2.c4 e6 is the normal order.)
• 1...c5 – most pure English lines come from the Symmetrical Variation and are quite hard to play and to understand.
• 1...c6 will usually either transpose into the Caro-Kann Defence or the Slav Defence.
• 1...f5, the Anglo-Dutch Defence, leads to sharp tactical lines for Black, but can open a powerful kingside attack. This is likely to transpose into the regular Dutch Defense after 2.d4.
• 1...b6 will in all likelihood transpose into the English Defence.
• 1...d5 is seldom played but may transpose into the Queen's Gambit or the Réti Opening.
• 1...b5 normally gives good chances for Black, even though the Halibut Gambit is considered unsound at the professional level.
• 1...g5, the Myers Defence, gives White a small advantage.

Statistics

Approximately chances

White win 37%, Draw 34%, Black win 29%.

Estimated next move popularity

Nf6 28%, e5 23%, e6 13%, c5 12%, g6 8%, c6 7%, f5 3%. Other moves less than 2%.

move	average	365Chess.com (big)	Chess Tempo (all)	chessgames.com	Lichess (masters)	Lichess (database)
...Nf6	28.2%	30.9	30.3	31.4	28.4	20.0
...e5	23.2	22.6	23.0	22.0	24.0	24.6
...e6	13.4	13.2	13.4	14.4	14.4	11.7
...c5	11.7	11.8	11.9	11.4	11.5	12.0
...g6	7.7	8.0	7.6	8.4	8.2	6.6
...c6	7.4	6.9	7.4	7.1	8.3	7.0
...f5	2.8	3.5	3.1	2.9	2.5	2.0
...b6	1.7	1.5	1.6	1.4	1.6	2.3
...d5	1.6	0.2	0.2	0.1	0.0	7.7
...d6	1.4	1.0	0.9	0.6	0.7	3.8
...Nc6	0.5	0.4	0.4	0.3	0.3	1.1
...b5	0.1	0.0	0.0	0.1	0.0	0.5
...a6	0.1	0.0	0.0	0.0	0.0	0.2
...g5	0.0	0.0	0.1	0.0	0.0	0.1
everything else	0.1	0.0	0.0	0.0	0.0	0.5

Theory table

1.c4
	1	2	3	4	5	6
Symmetrical Variation	c4 c5	Nf3 Nf6	g3 b6	Bg2 Bb7	O-O g6		=
Reversed Sicilian Defence	... e5	Nc3 Nc6	Nf3 Nf6	g3 d5	cxd5 Nxd5		∞
Agincourt Defence	... e6	Nc3 Bb4	Qb3 Nc6	Nf3 Nf6	a3 Bxc3		∞
Anglo-Slav Variation	... c6	Nf3 d5	g3 Nf6	Bg2 dxc4	O-O Nbd7		∞
Anglo-Indian Defence	... Nf6	Nc3 e6	e4 c5	e5 Ng8	Nf3 Nc6		∞
Great Snake Variation	... g6	e4 e5	d4 Nf6	dxe5 Nxe4	Bd3 Nc5		∞
English Defence	... b6	d4 e6	e4 Bb7				∞
Anglo-Dutch Defence	... f5	Nf3 Nf6	g3 g6	Bg2 Bg7	O-O O-O		∞
Anglo-Scandinavian Defence	... d5	cxd5 Qxd5	Nc3 Qa5				+=
Myers Defence	... g5	d4 Bg7?!	Bxg5! c5	Nf3 cxd4	Nxd4 Qb6	Nb5 Bxb2?!	+-
Halibut Gambit	... b5	cxb5 a6	e4! Bb7	Nc3 Nf6	e5 Nd5	Nf3 e6	+=

All possible Black's moves

Quick Navigation

Na6 a6 a5

b6 b5

Nc6 c6 c5

d6 d5

e6 e5

Nf6 f6 f5

g6 g5

Nh6 h6 h5

References

• Modern Chess Openings: MCO-14. 1999. Nick de Firmian, Walter Korn. ISBN 0-8129-3084-3.

• Kasparov, Garry, & Keene, Raymond 1989 Batsford chess openings 2. ISBN 0-8050-3409-9.

For explanation of theory tables, see theory table and for notation, see algebraic notation.