Claude Opus 4.8 vs Claude Fable 5 — Who Actually Wins? Real Benchmark Data (2026)

head to head

Claude Opus 4.8 vs Claude Fable 5

31 shared benchmarks

2

wins

1

ties

28

wins

39.4%

APEX-Agents

43.3%

45.2%

Agents' Last Exam

40.5%

27.2%

AutomationBench

29.1%

81.2%

BabyVision

90.5%

84.3%

BrowseComp

88.0%

80.5%

CharXiv

88.9%

59.0%

DeepSWE

70.0%

40.0%

ExploitBench

78.0%

80.0%

FrontierMath

87.0%

56.1%

FrontierMath Tier 4

87.8%

66.7%

FrontierSWE

86.6%

91.0%

GPQA Diamond

92.6%

49.8%

Humanity's Last Exam

53.3%

48.4%

JobBench

57.4%

86.7%

MATH-Vision

94.8%

77.8%

MCP-Atlas

84.7%

42.8%

MLS Bench

49.9%

78.9%

MMMU Pro

81.2%

63.9%

OfficeQA Pro

69.9%

87.9%

OmniDocBench

89.8%

47.2%

PerceptionBench

57.2%

34.1%

PostTrain Bench

41.4%

71.9%

Program Bench

76.8%

40.0%

SWE Marathon

35.0%

69.2%

SWE-bench Pro

80.3%

31.55%

SpreadsheetBench 2

34.7%

84.6%

Terminal-Bench 2.1

84.6%

59.9%

Toolathlon

61.7%

76.2%

Toolathlon-Verified

77.9%

39.1%

WorldVQA

56.7%

17.0%

ZeroBench

23.0%