Head-to-head comparison

GPT-5.5 vs. Grok 4.6

Compare published benchmark results from matching versions and cohorts, API pricing, and technical specifications. Any documented test setup differences remain visible.

shared result series: 68
distinct benchmarks: 23
latest retrieval: 2026-09-04

First modelSecond model

Specifications

General specifications

Release date, availability, context window, architecture, and published parameter counts at a glance. Undisclosed details remain marked as unavailable.

Specifications for GPT-5.5 and Grok 4.6
Attribute	GPT-5.5	Grok 4.6
Provider	OpenAI	xAI
Released	Apr 2026	Aug 12, 2026
Availability	Active	Active
Model type	Proprietary	Proprietary
Parameters	Not published	Not published
Architecture	Not published	Not published
Context window	1,050,000 tokens	500,000 tokens
Knowledge cutoff	December 1, 2025	February 1, 2026
Technical sources	Model	Model

Pricing

API pricing compared

The table compares official standard API rates per 1M tokens, including published cache pricing. Batch, fast, priority, regional surcharges, tool calls, and cloud platform pricing are excluded.

API pricing for GPT-5.5 and Grok 4.6
Price type	GPT-5.5	Grok 4.6
API input	$5 ≤272K / $10 >272K	$2 ≤200K / $4 >200K
API output	$30 ≤272K / $45 >272K	$6 ≤200K / $12 >200K
Cache read	$0.5 ≤272K / $1 >272K	$0.5 ≤200K / $1 >200K
Cache write (5 min.)	Not listed	Not listed
Cache write (1 hr.)	Not listed	Not listed
Price verified	07/30/2026 Source	08/16/2026 Source

GPT-5.5Grok 4.6

API inputUSD per 1M tokens, base tier

GPT-5.5$5

Grok 4.6$2

API outputUSD per 1M tokens, base tier

GPT-5.5$30

Grok 4.6$6

Cache readUSD per 1M tokens, base tier

GPT-5.5$0.5

Grok 4.6$0.5

Key to the marks:better valuebetter, but not conclusivetie

Pricing by provider

Direct developer pricing and provider endpoint tariffs routed through OpenRouter are listed separately. Prices are in USD per 1M tokens. Context-dependent direct tiers plus regional, Flex, Priority, and other OpenRouter tariffs remain individually identifiable.

Provider pricing for GPT-5.5 and Grok 4.6
Model	Provider	Purchase route and tariff	Input per 1M tokens	Output per 1M tokens	Source
GPT-5.5	OpenAI	Direct from developerUp to 272,000 context tokens	$5	$30	Source07/30/2026
	OpenAI	Direct from developerAbove 272,000 context tokens	$10	$45	Source07/30/2026
	Amazon Bedrock	Via OpenRouteramazon-bedrock/us-east-1	$5.5	$33	Source09/07/2026
	Azure	Via OpenRouterazure	$5	$30	Source09/07/2026
	Azure	Via OpenRouterazure/eu	$5.5	$33	Source09/07/2026
	Azure	Via OpenRouterazure/us	$5.5	$33	Source09/07/2026
	OpenAI	Via OpenRouteropenai	$5	$30	Source09/07/2026
	OpenAI	Via OpenRouteropenai/fast	$12.5	$75	Source09/07/2026
	OpenAI	Via OpenRouteropenai/flex	Lowest listed price: $2.5	Lowest listed price: $15	Source09/07/2026
Grok 4.6	xAI	Direct from developerUp to 200,000 context tokens	Lowest listed price: $2	Lowest listed price: $6	Source08/16/2026
	xAI	Direct from developerAbove 200,000 context tokens	$4	$12	Source08/16/2026
	Amazon Bedrock	Via OpenRouteramazon-bedrock/us-west-2	$2.2	$6.6	Source09/07/2026
	xAI	Via OpenRouterxai	Lowest listed price: $2	Lowest listed price: $6	Source09/07/2026
	xAI	Via OpenRouterxai/priority	$4	$12	Source09/07/2026
	xAI	Via OpenRouterxai/zdr	Lowest listed price: $2	Lowest listed price: $6	Source09/07/2026
	xAI	Via OpenRouterxai/zdr/priority	$4	$12	Source09/07/2026

Performance

Shared benchmarks

Only published results with the same benchmark version, task, metric, and comparison cohort are paired. Different reasoning levels, agents, harnesses, or output limits appear directly in the table.

Capability profile from matched benchmarks

Each axis averages directly matched benchmark families. A value of 100 means the stronger value within this pair, not a universal quality score.

GPT-5.5

Grok 4.6

Coding: 94.9 / 99.6 (5 benchmark families)

Reasoning: 99.2 / 99.2 (2 benchmark families)

Mathematics: 100 / 96.2 (1 benchmark family)

Knowledge: 99.3 / 99.7 (2 benchmark families)

Finance: 99.4 / 96.8 (6 benchmark families)

Legal: 76.9 / 99.6 (4 benchmark families)

Agentic tasks: 99.2 / 86.5 (3 benchmark families)

Productivity: 91.1 / 100 (1 benchmark family)

45 matched rows from 23 benchmark families were considered. The radar shows 8 of 12 comparable categories.

GPT-5.5Grok 4.6

Code MigrationOverall. Higher is better. No documented setup difference

GPT-5.545.161 %

Grok 4.644.572 %

CorpFin v2Overall. Higher is better. No documented setup difference

GPT-5.568.415 %

Grok 4.666.161 %

EMBOverall. Higher is better. No documented setup difference

GPT-5.564.543 %

Grok 4.662.727 %

Finance Agent (v2)Overall. Higher is better. No documented setup difference

GPT-5.551.76 %

Grok 4.653.682 %

GPQA DiamondOverall. Higher is better. No documented setup difference

GPT-5.593.182 %

Grok 4.694.697 %

Harvey's Legal Agent BenchmarkOverall · Task fully resolved. Higher is better. No documented setup difference

GPT-5.53.75 %

Grok 4.615.833 %

Legal Research BenchOverall · All-pass. Higher is better. No documented setup difference

GPT-5.540.385 %

Grok 4.648.077 %

LegalBenchOverall. Higher is better. No documented setup difference

GPT-5.586.515 %

Grok 4.686.307 %

LiveCodeBench v6Overall. Higher is better. No documented setup difference

GPT-5.585.296 %

Grok 4.688.224 %

LMArena Text, Style ControlOverall. Higher is better. Test setup not documented as identical

GPT-5.51,477.235

Grok 4.61,461.115

MedCodeOverall. Higher is better. No documented setup difference

GPT-5.549.1 %

Grok 4.644.712 %

MedScribeOverall. Higher is better. No documented setup difference

GPT-5.586.868 %

Grok 4.686.534 %

Key to the marks:better valuebetter, but not conclusivetie

How to read this comparison

Winning one benchmark is not an overall verdict

Your workload, budget, and required context length matter most. A coding benchmark says little about visual understanding or agent performance.

The standard price table uses direct developer rates. The provider comparison labels OpenRouter endpoints, regions, and special tariffs separately.

Every result links to its measurement source and retrieval date. Labels distinguish vendor reports, official benchmark leaderboards, and independent evaluations. Disputed or archived results are excluded.

More matchups

Compare GPT-5.5 and Grok 4.6 with other leading models using the same data and benchmark logic.

View the complete LLM comparison

Benchmark scores for GPT-5.5 and Grok 4.6
Benchmark and task	GPT-5.5	Grok 4.6	Source
Code MigrationOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner45.161 %	44.572 %	Vals AI Source details Data as of: 09/03/2026
CorpFin v2Overall Test details No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better	Winner68.415 %	66.161 %	Vals AI Source details Data as of: 08/12/2026
EMBOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner64.543 %	62.727 %	Vals AI Source details Data as of: 09/03/2026
Finance Agent (v2)Overall Test details No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better	51.76 %	Winner53.682 %	Vals AI Source details Data as of: 09/03/2026
GPQA DiamondOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	93.182 %	Winner94.697 %	Vals AI Source details Data as of: 09/01/2026
Harvey's Legal Agent BenchmarkOverall · Task fully resolved Test details No documented difference in the test setupVersion: 1Metric: task resolution rateScoring: Higher is better	3.75 %	Winner15.833 %	Vals AI Source details Data as of: 09/03/2026
Legal Research BenchOverall · All-pass Test details No documented difference in the test setupVersion: 1Metric: all-pass rateScoring: Higher is better	40.385 %	Winner48.077 %	Vals AI Source details Data as of: 09/03/2026
LegalBenchOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner86.515 %	86.307 %	Vals AI Source details Data as of: 09/01/2026
LiveCodeBench v6Overall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	85.296 %	Winner88.224 %	Vals AI Source details Data as of: 09/01/2026
LMArena Text, Style ControlOverall Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 64,686 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 3,453 anonymous pairwise votes.	Higher measured value1,477.235 95% confidence interval: ±3.839The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,461.115 95% confidence interval: ±10.144The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
MedCodeOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner49.1 %	44.712 %	Vals AI Source details Data as of: 09/03/2026
MedScribeOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner86.868 %	86.534 %	Vals AI Source details Data as of: 09/03/2026
MMLU-ProOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	88.144 %	Winner89.4 %	Vals AI Source details Data as of: 09/01/2026
MortgageTaxOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner68.76 %	64.189 %	Vals AI Source details Data as of: 09/01/2026
Public Benefits Bench v1.1Overall Test details No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is better	60.893 %	Winner66.847 %	Vals AI Source details Data as of: 09/01/2026
SAGEOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner51.532 %	28.9 %	Vals AI Source details Data as of: 09/03/2026
SkillsBenchOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands	Winner62.209 %	55.766 %	Vals AI Source details Data as of: 09/01/2026
SWE-bench VerifiedOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	82.6 %	Winner95.6 %	Vals AI Source details Data as of: 09/01/2026
TaxEval v2Overall Test details No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better	Winner74.98 %	71.096 %	Vals AI Source details Data as of: 09/01/2026
Terminal-Bench 2.1Overall Test details No documented difference in the test setupVersion: 2.1Metric: accuracyScoring: Higher is better	76.404 %	Winner78.277 %	Vals AI Source details Data as of: 09/03/2026
Time Horizon Index: KSPOverall Test details No documented difference in the test setupVersion: 1Metric: progressScoring: Higher is better	Winner8.333 %	5.833 %	Vals AI Source details Data as of: 08/20/2026
Vals IndexOverall Test details No documented difference in the test setupVersion: 2Metric: weighted index scoreScoring: Higher is better	57.411 %	Winner59.167 %	Vals AI Source details Data as of: 09/03/2026
Vibe Code Bench v1.1Overall Test details No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands	69.847 %	Winner76.239 %	Vals AI Source details Data as of: 09/03/2026
LMArena Text, Style ControlOverall Test details No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 63,265 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 3,453 anonymous pairwise votes.	Winner1,482.334 95% confidence interval: ±3.856The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,461.115 95% confidence interval: ±10.144The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlBusiness, management and finance Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 12,904 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 705 anonymous pairwise votes.	Higher measured value1,485.915 95% confidence interval: ±6.577The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,467.318 95% confidence interval: ±22.146The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlBusiness, management and finance Test details No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 12,594 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 705 anonymous pairwise votes.	No clear lead1,489.993 95% confidence interval: ±6.59The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,467.318 95% confidence interval: ±22.146The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlChinese Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,552 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 291 anonymous pairwise votes.	1,530.095 95% confidence interval: ±11.053The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	Higher measured value1,538.386 95% confidence interval: ±33.69The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlChinese Test details No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,648 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 291 anonymous pairwise votes.	1,515.679 95% confidence interval: ±10.674The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	No clear lead1,538.386 95% confidence interval: ±33.69The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlCoding Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 18,325 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 838 anonymous pairwise votes.	1,508.939 95% confidence interval: ±5.848The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	Higher measured value1,510.751 95% confidence interval: ±20.826The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlCoding Test details No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 17,606 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 838 anonymous pairwise votes.	No clear lead1,520.129 95% confidence interval: ±5.918The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,510.751 95% confidence interval: ±20.826The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlCreative writing Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 11,878 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 651 anonymous pairwise votes.	1,448.376 95% confidence interval: ±6.88The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	Higher measured value1,458.096 95% confidence interval: ±23.926The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlCreative writing Test details No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 11,556 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 651 anonymous pairwise votes.	1,452.482 95% confidence interval: ±6.902The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	No clear lead1,458.096 95% confidence interval: ±23.926The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlEnglish Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 29,547 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 1,434 anonymous pairwise votes.	Higher measured value1,482.081 95% confidence interval: ±4.938The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,459.46 95% confidence interval: ±15.407The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlEnglish Test details No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 28,840 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 1,434 anonymous pairwise votes.	Winner1,484.772 95% confidence interval: ±4.944The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,459.46 95% confidence interval: ±15.407The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlEntertainment, sports and media Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 15,289 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 777 anonymous pairwise votes.	Higher measured value1,446.376 95% confidence interval: ±6.282The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,443.149 95% confidence interval: ±21.821The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlEntertainment, sports and media Test details No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 14,828 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 777 anonymous pairwise votes.	No clear lead1,450.494 95% confidence interval: ±6.344The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,443.149 95% confidence interval: ±21.821The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlExcluding ties Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 49,327 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 2,522 anonymous pairwise votes.	Higher measured value1,486.307 95% confidence interval: ±5.005The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,465.128 95% confidence interval: ±14.002The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlExcluding ties Test details No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 47,980 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 2,522 anonymous pairwise votes.	Winner1,493.228 95% confidence interval: ±5.003The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,465.128 95% confidence interval: ±14.002The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlExpert prompts Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 6,796 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 401 anonymous pairwise votes.	Higher measured value1,511.055 95% confidence interval: ±8.262The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,479.844 95% confidence interval: ±28.841The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
LMArena Text, Style ControlExpert prompts Test details No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control Grok 4.6: Snapshot: grok-4.6-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 6,546 anonymous pairwise votes.Grok 4.6: Style-controlled Arena rating from 401 anonymous pairwise votes.	No clear lead1,513.567 95% confidence interval: ±8.306The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	1,479.844 95% confidence interval: ±28.841The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026