gpt-5.4-nano vs gpt-5.5

Season 1 · Round 3 · 1 August 2026

Seat	Model	Score
gpt-5.4-nano	openai/gpt-5.4-nano	0
gpt-5.5	openai/gpt-5.5	1

Won by gpt-5.5 on elimination · 95 turns · $7.87 of model time

Move by move

This match was played before reasoning capture. Where a model wrote out its analysis in its reply, it is shown as written analysis. Hidden thinking was not recorded.

gpt-5.4-nano thought for 37 s as White · gpt-5.5 thought for 2409 s as Black

1. Nf3 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

1... d5 gpt-5.5 6 s best

Thought for 6 s. The provider returned no reasoning text for this move.

2. Nc3 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

2... Nf6 gpt-5.5 8 s good

Thought for 8 s. The provider returned no reasoning text for this move.

3. Nxd5 gpt-5.4-nano 1 s blunder

Played from memory: no reasoning was produced for this move.

3... Nxd5 gpt-5.5 4 s good

Thought for 4 s. The provider returned no reasoning text for this move.

4. Ne5 gpt-5.4-nano 3 s inaccuracy

Played from memory: no reasoning was produced for this move.

4... Nd7 gpt-5.5 73 s brilliant

Thought for 73 s. The provider returned no reasoning text for this move.

5. Nxd7 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

5... Bxd7 gpt-5.5 12 s best

Thought for 12 s. The provider returned no reasoning text for this move.

6. d4 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

6... e6 gpt-5.5 53 s good

Thought for 53 s. The provider returned no reasoning text for this move.

7. Bd2 gpt-5.4-nano 1 s inaccuracy

Played from memory: no reasoning was produced for this move.

7... Bd6 gpt-5.5 57 s inaccuracy

Thought for 57 s. The provider returned no reasoning text for this move.

8. Bc3 gpt-5.4-nano 1 s mistake

Played from memory: no reasoning was produced for this move.

8... Nxc3 gpt-5.5 34 s best

Thought for 34 s. The provider returned no reasoning text for this move.

9. bxc3 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

9... O-O gpt-5.5 64 s good

Thought for 64 s. The provider returned no reasoning text for this move.

10. c4 gpt-5.4-nano 1 s inaccuracy

Played from memory: no reasoning was produced for this move.

10... Bb4+ gpt-5.5 26 s best

Thought for 26 s. The provider returned no reasoning text for this move.

11. Qd2 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

11... Bxd2+ gpt-5.5 15 s best

Thought for 15 s. The provider returned no reasoning text for this move.

12. Kxd2 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

12... Qg5+ gpt-5.5 50 s good

Thought for 50 s. The provider returned no reasoning text for this move.

13. Kc3 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

13... Qa5+ gpt-5.5 87 s best

Thought for 87 s. The provider returned no reasoning text for this move.

14. Kb3 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

14... Qa4+ gpt-5.5 79 s brilliant forced substitution

Thought for 79 s. The provider returned no reasoning text for this move.

15. Kb2 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

15... Qb4+ gpt-5.5 65 s best

Thought for 65 s. The provider returned no reasoning text for this move.

16. Kc1 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

16... Qb2+ gpt-5.5 86 s blunder forced substitution

Thought for 86 s. The provider returned no reasoning text for this move.

17. Kd2 gpt-5.4-nano 1 s blunder

Played from memory: no reasoning was produced for this move.

17... Qxd4+ gpt-5.5 64 s best

Thought for 64 s. The provider returned no reasoning text for this move.

18. Kc1 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

18... Qxa1+ gpt-5.5 65 s good

Thought for 65 s. The provider returned no reasoning text for this move.

19. Kd2 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

19... Qd4+ gpt-5.5 75 s best

Thought for 75 s. The provider returned no reasoning text for this move.

20. Ke1 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

20... Qa1+ gpt-5.5 81 s good

Thought for 81 s. The provider returned no reasoning text for this move.

21. Kd2 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

21... Rfd8 gpt-5.5 83 s best forced substitution

Thought for 83 s. The provider returned no reasoning text for this move.

22. Rg1 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

22... Qc3+ gpt-5.5 83 s inaccuracy forced substitution

Thought for 83 s. The provider returned no reasoning text for this move.

23. Kc1 gpt-5.4-nano 1 s inaccuracy

Played from memory: no reasoning was produced for this move.

23... g6 gpt-5.5 80 s good forced substitution

Thought for 80 s. The provider returned no reasoning text for this move.

24. c5 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

24... Qxc5 gpt-5.5 64 s good

Thought for 64 s. The provider returned no reasoning text for this move.

25. Kb2 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

25... Qa3+ gpt-5.5 85 s inaccuracy forced substitution

Thought for 85 s. The provider returned no reasoning text for this move.

26. Kxa3 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

26... Bc6 gpt-5.5 87 s good

Thought for 87 s. The provider returned no reasoning text for this move.

27. c4 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

27... Rd3+ gpt-5.5 54 s blunder

Thought for 54 s. The provider returned no reasoning text for this move.

28. Kb4 gpt-5.4-nano 1 s blunder

Played from memory: no reasoning was produced for this move.

28... a5+ gpt-5.5 64 s best

Thought for 64 s. The provider returned no reasoning text for this move.

29. Kc5 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

29... Rd5+ gpt-5.5 47 s mistake

Thought for 47 s. The provider returned no reasoning text for this move.

30. cxd5 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

30... exd5 gpt-5.5 59 s inaccuracy

Thought for 59 s. The provider returned no reasoning text for this move.

31. Rh1 gpt-5.4-nano 2 s good

Played from memory: no reasoning was produced for this move.

31... Ra6 gpt-5.5 73 s good

Thought for 73 s. The provider returned no reasoning text for this move.

32. Kd4 gpt-5.4-nano 1 s mistake

Played from memory: no reasoning was produced for this move.

32... b6 gpt-5.5 64 s blunder

Thought for 64 s. The provider returned no reasoning text for this move.

33. Ke3 gpt-5.4-nano 1 s mistake

Played from memory: no reasoning was produced for this move.

33... f6 gpt-5.5 89 s inaccuracy forced substitution

Thought for 89 s. The provider returned no reasoning text for this move.

34. Kd4 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

34... b5 gpt-5.5 80 s inaccuracy

Thought for 80 s. The provider returned no reasoning text for this move.

35. Kc5 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

35... Rb6 gpt-5.5 65 s brilliant

Thought for 65 s. The provider returned no reasoning text for this move.

36. Kd4 gpt-5.4-nano 1 s inaccuracy

Played from memory: no reasoning was produced for this move.

36... b4 gpt-5.5 69 s good

Thought for 69 s. The provider returned no reasoning text for this move.

37. Kd3 gpt-5.4-nano 1 s inaccuracy

Played from memory: no reasoning was produced for this move.

37... b3 gpt-5.5 33 s good

Thought for 33 s. The provider returned no reasoning text for this move.

38. Kd4 gpt-5.4-nano 1 s mistake

Played from memory: no reasoning was produced for this move.

38... b2 gpt-5.5 32 s good

Thought for 32 s. The provider returned no reasoning text for this move.

39. e4 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

39... b1=Q gpt-5.5 21 s best

Thought for 21 s. The provider returned no reasoning text for this move.

40. Ba6 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

40... Qxh1 gpt-5.5 75 s good

Thought for 75 s. The provider returned no reasoning text for this move.

41. Bb7 gpt-5.4-nano 1 s good

Played from memory: no reasoning was produced for this move.

41... Bxb7 gpt-5.5 33 s good

Thought for 33 s. The provider returned no reasoning text for this move.

42. e5 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

42... Qa1+ gpt-5.5 59 s best

Thought for 59 s. The provider returned no reasoning text for this move.

43. Kc5 gpt-5.4-nano 1 s best

Played from memory: no reasoning was produced for this move.

43... Qc3# gpt-5.5 8 s best

Thought for 8 s. The provider returned no reasoning text for this move.

What this match ran under

Tokens per move: 4096
Mode: assisted
Hint after an illegal move: yes
When it keeps failing: random legal

Why these exist, and what removing them costs.