Skip to main content

Best Proprietary LLMs in 2026

Top proprietary/closed-source AI models ranked by benchmark performance.

Unless noted otherwise, ranking surfaces on this page use BenchLM's provisional leaderboard lane rather than the stricter sourced-only verified leaderboard.

Bottom line: Claude Mythos Preview leads proprietary models overall, with Gemini 3.1 Pro and GPT-5.4 close behind. The top tier is competitive — choice often comes down to pricing, latency, and API ecosystem.

According to BenchLM.ai, Claude Mythos Preview leads this ranking with a score of 99, followed by GPT-5.4 (94) and Gemini 3.1 Pro (94). There is meaningful separation between the top models, suggesting genuine performance differences.

All models in this ranking are proprietary. No open-weight alternatives are available for this category.

This ranking is based on provisional overall weighted scores across BenchLM.ai's scoring formula tracked by BenchLM.ai. For detailed model profiles, click any model name below. To compare two specific models head-to-head, use the "vs #" links.

What changed

Claude Mythos Preview entered at #1 across proprietary models with the highest overall score.

Gemini 3.1 Pro strong #2 among proprietary models — best non-reasoning option.

GPT-5.4 leads knowledge benchmarks at 98 and holds a strong #3.

How to choose

Full Rankings (60 models)

Claude Mythos Preview
Anthropic·Proprietary·1M

99

prov. overall

GPT-5.4
OpenAI·Proprietary·1.05M

94

prov. overall

Gemini 3.1 Pro
Google·Proprietary·1M

94

prov. overall

4
Claude Opus 4.6
Anthropic·Proprietary·1M

92

prov. overall

5
GPT-5.4 Pro
OpenAI·Proprietary·1.05M

92

prov. overall

6
GPT-5.3 Codex
OpenAI·Proprietary·400K

89

prov. overall

7
Gemini 3 Pro Deep Think
Google·Proprietary·2M

87

prov. overall

8
Claude Sonnet 4.6
Anthropic·Proprietary·200K

86

prov. overall

9
GPT-5.2
OpenAI·Proprietary·400K

84

prov. overall

10
Gemini 3 Pro
Google·Proprietary·2M

83

prov. overall

11
GPT-5.1
OpenAI·Proprietary·200K

81

prov. overall

12
Grok 4.1
xAI·Proprietary·1M

81

prov. overall

13
Claude Opus 4.5
Anthropic·Proprietary·200K

80

prov. overall

14
GPT-5 (high)
OpenAI·Proprietary·128K

80

prov. overall

15
GPT-5.2-Codex
OpenAI·Proprietary·400K

80

prov. overall

16
GPT-5.1-Codex-Max
OpenAI·Proprietary·400K

79

prov. overall

17
Kimi K2.5 (Reasoning)
Moonshot AI·Proprietary·128K

79

prov. overall

18
Grok 4.20
xAI·Proprietary·2M

78

prov. overall

19
Qwen3.6 Plus
Alibaba·Proprietary·1M

77

prov. overall

20
GPT-5 (medium)
OpenAI·Proprietary·128K

74

prov. overall

21
GPT-5.4 mini
OpenAI·Proprietary·400K

73

prov. overall

22
Grok 4.1 Fast
xAI·Proprietary·1M

72

prov. overall

23
o1-preview
OpenAI·Proprietary·200K

69

prov. overall

24
Claude Sonnet 4.5
Anthropic·Proprietary·200K

68

prov. overall

25
Gemini 2.5 Pro
Google·Proprietary·1M

67

prov. overall

26
Gemini 3 Flash
Google·Proprietary·1M

67

prov. overall

27
Grok 4
xAI·Proprietary·128K

67

prov. overall

28
GPT-4.1
OpenAI·Proprietary·1M

61

prov. overall

29
Claude Haiku 4.5
Anthropic·Proprietary·200K

60

prov. overall

30
o1
OpenAI·Proprietary·200K

60

prov. overall

31
o3
OpenAI·Proprietary·200K

60

prov. overall

32
o3-pro
OpenAI·Proprietary·200K

60

prov. overall

33
o3-mini
OpenAI·Proprietary·200K

58

prov. overall

34
Claude 4.1 Opus
Anthropic·Proprietary·200K

53

prov. overall

35
Claude 4 Sonnet
Anthropic·Proprietary·200K

52

prov. overall

36
Mistral Large 3
Mistral·Proprietary·128K

52

prov. overall

37
Gemini 3.1 Flash-Lite
Google·Proprietary·1M

51

prov. overall

38
GPT-4.1 mini
OpenAI·Proprietary·1M

47

prov. overall

39
o4-mini (high)
OpenAI·Proprietary·200K

46

prov. overall

40
Claude 4.1 Opus Thinking
Anthropic·Proprietary·200K

45

prov. overall

41
GPT-4o mini
OpenAI·Proprietary·128K

45

prov. overall

42
Kimi K2
Moonshot AI·Proprietary·128K

44

prov. overall

43
Claude 3.5 Sonnet
Anthropic·Proprietary·200K

42

prov. overall

44
Grok Code Fast 1
xAI·Proprietary·256K

42

prov. overall

45
Gemini 2.5 Flash
Google·Proprietary·1M

41

prov. overall

46
GPT-4o
OpenAI·Proprietary·128K

41

prov. overall

47
Mistral Large 2
Mistral·Proprietary·128K

40

prov. overall

48
Gemini 1.5 Pro
Google·Proprietary·2M

38

prov. overall

49
Claude 3 Opus
Anthropic·Proprietary·200K

37

prov. overall

50
Grok 3 [Beta]
xAI·Proprietary·128K

34

prov. overall

51
o1-pro
OpenAI·Proprietary·200K

30

prov. overall

52
GLM-4.5
Z.AI·Proprietary·128K

29

prov. overall

53
GPT-4.1 nano
OpenAI·Proprietary·1M

28

prov. overall

54
GPT-4 Turbo
OpenAI·Proprietary·128K

27

prov. overall

55
Claude 3 Haiku
Anthropic·Proprietary·200K

25

prov. overall

56
Gemini 1.0 Pro
Google·Proprietary·32K

25

prov. overall

57
Z-1
Z·Proprietary·128K

25

prov. overall

58
Moonshot v1
Moonshot AI·Proprietary·128K

24

prov. overall

59
GLM-4.5-Air
Z.AI·Proprietary·128K

22

prov. overall

60
Nova Pro
Amazon·Proprietary·128K

11

prov. overall

These rankings update weekly

Get notified when models move. One email a week with what changed and why.

Free. No spam. Unsubscribe anytime.

Key Takeaways

The top model is Claude Mythos Preview by Anthropic with a provisional score of 99.

60 models are included in this ranking.

Score in Context

What these scores mean

Models are ranked by the same overall BenchLM score used across all leaderboards. Comparing within proprietary's lineup helps identify which model fits your use case and budget.

Known limitations

This page only shows proprietary models. Cross-provider comparison requires the overall or category-specific leaderboards. Newer models may have limited benchmark coverage initially.

Last updated: April 10, 2026

The AI models change fast. We track them for you.

For engineers, researchers, and the plain curious — a weekly brief on new models, ranking shifts, and pricing changes.

Free. No spam. Unsubscribe anytime.