Legal Research Bench leaderboard (Oct 2026): AI model scores

Name: Legal Research Bench leaderboard: AI model scores
Creator: Vals AI

As of 19 Oct 2026, the highest reported Anthropic score on Legal Research Bench is shared by Claude Opus 5 (Anthropic) and Claude Fable 5.1 (Anthropic) at 55.29%, #2 on that leaderboard, per Vals AI.

What it measures

Agents doing legal research tasks across diverse areas of US law.

AI agents research questions across areas of US law; a task only counts if every required point is right.

What the score means

All-Pass: tasks where every grading check passed

Share of research tasks where the answer met every grading point.

Results from published AI leaderboards. Compare models within each benchmark; scores from different tests aren’t directly comparable. How we collect these results

Scores by model

Run by Vals AI. Leaderboard dated 19 Oct 2026. Last checked 22 Oct 2026. Showing top 25 of 82 models listed.

Highlight a provider: Anthropic OpenAI Google xAI Meta DeepSeek Alibaba Z.ai Moonshot Xiaomi

Highlighting Anthropic models. Other providers are dimmed. Show all providers

Anthropic
OpenAI
Google
xAI
Meta
DeepSeek
Alibaba
Z.ai
Moonshot
Xiaomi
Other

All-Pass: Share of research tasks where the answer met every grading point.
Cost per test (USD): Average API cost to run one task, as published.

All scores

Legal Research Bench scores, Anthropic models highlighted
Rank	Model	Provider	All-Pass	Cost per test (USD)	Price in / out ($/1M tokens)
1	Muse Spark 1.3 Max	Meta	55.29%	$0.59	$1.25 / $4.25
2	Claude Opus 5	Anthropic	55.29%	$6.76	$5 / $25
3	Claude Fable 5.1	Anthropic	55.29%	$23	$10 / $50
4	Gemini 4 Argon	Google	54.81%	$6.45	$4 / $20
5	Wonder Full	Meta	53.37%	$3.60	$4 / $20
6	Wonder	Meta	50.48%	$3.98	$4 / $20
7	Claude Opus 5.5	Anthropic	50.48%	$25	$4 / $20
8	Claude Fable 5	Anthropic	49.52%	$9.79	$10 / $50
9	GLM 5.3	Z.ai	49.04%	$2.24	$1.4 / $4.4
10	Grok 4.6	xAI	48.08%	$1.53	$2 / $6

Show 15 more rows

Rank	Model	Provider	All-Pass	Cost per test (USD)	Price in / out ($/1M tokens)
11	GPT-5.6 Sol	OpenAI	48.08%	$22	$4 / $20
12	Claude Sonnet 5.5	Anthropic	48.08%	$15	$2 / $10
13	Qwen 3.8 Max	Alibaba	47.60%	$2.49	$2 / $6
14	Grok 4.7	xAI	47.12%	$4.92	$2 / $6
15	MiMo V2.6 Pro	Xiaomi	47.12%	$0.18	$0.435 / $0.87
16	Kimi K3	Moonshot	46.15%	$3.47	$3 / $15
17	DeepSeek V4.1 Flash 1017	DeepSeek	45.19%	$0.70	$0.3 / $1.2
18	GLM 5.3 Flash	Z.ai	45.19%	$0.12	$0.075 / $0.25
19	Hy4 Preview	Other	45.19%	$0.85	$0.834 / $2.501
20	Ember-1	Other	44.71%	$3.67	$3 / $15
21	Muse Spark 1.2	Meta	43.75%	$0.51	$1.25 / $4.25
22	Claude Opus 4.8	Anthropic	43.75%	$2.82	$5 / $25
23	Claude Haiku 5.5	Anthropic	43.27%	$1.63	$0.1 / $0.5
24	Claude Sonnet 5	Anthropic	41.83%	$2.72	$2 / $10
25	GLM Legal	Z.ai	41.83%	$0.050	$0.075 / $0.25

Source: Vals AI leaderboard ↗

Best-ranked Anthropic model here: Claude Opus 5 (Anthropic). Try prompts for Claude →