ecocodes
Volume C · Open games and the French DefenseC01 ›
a1b2c3d4e5f6g7h8
Reference position · White to move

C00 French Defense

Also filed here: Rat Defense.

C00 holds 43 named lines from two openings, most of them (42) under French Defense. It leaves B00 (King’s Pawn Game) with 1...e6. Lines of 21 other codes continue from its position, the widest spread of the 19 French Defense codes. With 43 named lines it is the largest code of the 19 French Defense codes. At two plies, its reference line is the shortest of the 19 French Defense codes.

Score sheet
#WhiteBlack
1e4e6

The move that completes C00

The reference line of C01 plays all of these moves and continues beyond them; C00 is the position reached at 1...e6.

  1. 1...e6 The e-pawn advances to e6, covering d5 and f5, opening a line for the queen on d8 and the bishop on f8.

Lines filed under C00

They begin with two different first moves.

NameAfter the shared startPliesAt the end
French Defense1.e4 e62
French Defense: Banzai-Leong Gambit1.e4 e6 2.b43
French Defense: Bird Invitation1.e4 e6 2.Bb53
French Defense: Chigorin Variation1.e4 e6 2.Qe23
French Defense: Horwitz Attack1.e4 e6 2.b33
French Defense: King’s Indian Attack1.e4 e6 2.d33
French Defense: Knight Variation1.e4 e6 2.Nf33
French Defense: La Bourdonnais Variation1.e4 e6 2.f43
French Defense: Normal Variation1.e4 e6 2.d43
French Defense: Queen’s Knight1.e4 e6 2.Nc33
French Defense: Réti-Spielmann Attack1.e4 e6 2.g33
French Defense: Steiner Variation1.e4 e6 2.c43
French Defense: Steinitz Attack1.e4 e6 2.e53
French Defense1.e4 e6 2.d4 d54
French Defense: Baeuerle Gambit1.e4 e6 2.d4 b54
French Defense: Franco-Hiva Gambit1.e4 e6 2.d4 f54
French Defense: Franco-Sicilian Defense1.e4 e6 2.d4 c54
French Defense: King’s Indian Attack, Franco-Hiva Gambit1.e4 e6 2.d3 f54
French Defense: Knight Variation, Franco-Hiva Gambit1.e4 e6 2.Nf3 f54
French Defense: Mediterranean Defense1.e4 e6 2.d4 Nf64
French Defense: St. George Defense1.e4 e6 2.d4 a64
Rat Defense: Small Center Defense1.d4 e6 2.e4 d64
French Defense: Alapin Gambit1.e4 e6 2.d4 d5 3.Be35
French Defense: Banzai-Leong Gambit, Pinova Gambit1.e4 e6 2.b4 Bxb4 3.e55Black +1
French Defense: Diemer-Duhm Gambit1.e4 e6 2.d4 d5 3.c45
French Defense: Franco-Hiva Gambit Accepted1.e4 e6 2.d4 f5 3.exf55White +1
French Defense: Horwitz Attack, Papa-Ticulat Gambit1.e4 e6 2.b3 d5 3.Bb25
French Defense: Morphy Gambit1.e4 e6 2.d4 d5 3.Nh35
French Defense: Pelikan Variation1.e4 e6 2.Nc3 d5 3.f45
French Defense: Perseus Gambit1.e4 e6 2.d4 d5 3.Nf35
French Defense: Schlechter Variation1.e4 e6 2.d4 d5 3.Bd35
French Defense: St. George Defense, Three Pawn Attack1.e4 e6 2.d4 a6 3.c45
French Defense: Two Knights Variation1.e4 e6 2.Nf3 d5 3.Nc35
French Defense: Diemer-Duhm Gambit Accepted1.e4 e6 2.d4 d5 3.c4 dxe46Black +1
French Defense: La Bourdonnais Variation, Reuter Gambit1.e4 e6 2.f4 d5 3.Nf3 dxe46Black +1
French Defense: St. George Defense, Sanky-George Gambit1.e4 e6 2.d4 a6 3.c4 b56
French Defense: Carlson Gambit1.e4 e6 2.d4 d5 3.Nf3 dxe4 4.Ne57Black +1
French Defense: Orthoschnapp Gambit1.e4 e6 2.c4 d5 3.cxd5 exd5 4.Qb37
French Defense: Wing Gambit1.e4 e6 2.Nf3 d5 3.e5 c5 4.b47
French Defense: Hoffmann Gambit1.e4 e6 2.d4 d5 3.Qe2 e5 4.f4 exf48Black +1
French Defense: St. George Defense, St. George Gambit1.e4 e6 2.d4 a6 3.c4 b5 4.cxb5 axb58
French Defense: Reversed Philidor Formation1.e4 e6 2.d3 d5 3.Nd2 Nf6 4.Ngf3 Nc6 5.Be29
French Defense: St. George Defense, Traditional Line1.e4 e6 2.d4 a6 3.Nf3 b5 4.Bd3 c5 5.c3 Bb7 6.O-O Nf612White castled

The road to C00

  1. 1.e4B00 King’s Pawn Game
  2. 1...e6C00

The position after 1...e6

White is to move and has 30 legal moves.

WhiteBlackMaterial (pawn units)3939Minor pieces developed00Moves spent on pawns11Pawns on d4, e4, d5, e510Squares attacked in the other half53not castlednot castled

Codes that branch off from C00

The reference lines of four other codes leave C00 from the position after 2...d5, each with its own moves.

CodeMovesReference line
C013.exd5French Defense: Exchange Variation
C023.e5French Defense: Advance Variation
C033.Nd2French Defense: Tarrasch Variation
C103.Nc3French Defense: Paulsen Variation

Closest boards in other codes

CodeLineDiffers on
C20King’s Pawn Gametwo squares: e5, e6
C21Center Game Acceptedthree squares: d2, d4, e6
C33King’s Gambit Acceptedthree squares: f2, f4, e6
A13English Opening: Agincourt Defensefour squares: c2, e2, c4, e4
B01Scandinavian Defensefour squares: d5, e6, d7, e7
B02Alekhine Defensefour squares: e6, f6, e7, g8
B06Modern Defensefour squares: e6, g6, e7, g7

Where lines continue from here

Besides the codes above, they belong to A08, A43, C04, C05, C06, C07, C08, C09, C11, C12, C13, C14, C15, C16, C17, C18, C19.

Volume A

  1. 00
  2. 01
  3. 02
  4. 03
  5. 04
  6. 05
  7. 06
  8. 07
  9. 08
  10. 09
  11. 10
  12. 11
  13. 12
  14. 13
  15. 14
  16. 15
  17. 16
  18. 17
  19. 18
  20. 19
  21. 20
  22. 21
  23. 22
  24. 23
  25. 24
  26. 25
  27. 26
  28. 27
  29. 28
  30. 29
  31. 30
  32. 31
  33. 32
  34. 33
  35. 34
  36. 35
  37. 36
  38. 37
  39. 38
  40. 39
  41. 40
  42. 41
  43. 42
  44. 43
  45. 44
  46. 45
  47. 46
  48. 47
  49. 48
  50. 49
  51. 50
  52. 51
  53. 52
  54. 53
  55. 54
  56. 55
  57. 56
  58. 57
  59. 58
  60. 59
  61. 60
  62. 61
  63. 62
  64. 63
  65. 64
  66. 65
  67. 66
  68. 67
  69. 68
  70. 69
  71. 70
  72. 71
  73. 72
  74. 73
  75. 74
  76. 75
  77. 76
  78. 77
  79. 78
  80. 79
  81. 80
  82. 81
  83. 82
  84. 83
  85. 84
  86. 85
  87. 86
  88. 87
  89. 88
  90. 89
  91. 90
  92. 91
  93. 92
  94. 93
  95. 94
  96. 95
  97. 96
  98. 97
  99. 98
  100. 99

Volume C

  1. 00
  2. 01
  3. 02
  4. 03
  5. 04
  6. 05
  7. 06
  8. 07
  9. 08
  10. 09
  11. 10
  12. 11
  13. 12
  14. 13
  15. 14
  16. 15
  17. 16
  18. 17
  19. 18
  20. 19
  21. 20
  22. 21
  23. 22
  24. 23
  25. 24
  26. 25
  27. 26
  28. 27
  29. 28
  30. 29
  31. 30
  32. 31
  33. 32
  34. 33
  35. 34
  36. 35
  37. 36
  38. 37
  39. 38
  40. 39
  41. 40
  42. 41
  43. 42
  44. 43
  45. 44
  46. 45
  47. 46
  48. 47
  49. 48
  50. 49
  51. 50
  52. 51
  53. 52
  54. 53
  55. 54
  56. 55
  57. 56
  58. 57
  59. 58
  60. 59
  61. 60
  62. 61
  63. 62
  64. 63
  65. 64
  66. 65
  67. 66
  68. 67
  69. 68
  70. 69
  71. 70
  72. 71
  73. 72
  74. 73
  75. 74
  76. 75
  77. 76
  78. 77
  79. 78
  80. 79
  81. 80
  82. 81
  83. 82
  84. 83
  85. 84
  86. 85
  87. 86
  88. 87
  89. 88
  90. 89
  91. 90
  92. 91
  93. 92
  94. 93
  95. 94
  96. 95
  97. 96
  98. 97
  99. 98
  100. 99

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