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Model compare

GPT-5.1 vs GPT-5.6 Sol

The readout for GPT-5.1 and GPT-5.6 Sol, before the detailed comparison sheet.

Model A

GPT-5.1

OpenAI

Contender
vs

Model B

GPT-5.6 Sol

OpenAI

Leading

Key Takeaways

Weighted outcome: GPT-5.6 Sol. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.

Decision read

GPT-5.6 Sol

GPT-5.6 Sol has the higher weighted result; Model A / B score 29.3 to 70.7.

Evidence depth

117 data points

Includes 26 benchmark rows, 0 audit samples, and 10 provider examples.

Selection signal

Start with GPT-5.6 Sol

The charts below split 36 high-signal samples across speed, scores, and audit health.

Change comparison

Switch either side of this report to compare another model with the same LMSpeed data pipeline.

Select a different model to open a new comparison URL.

Comparison sheet

This report only uses LMSpeed data for GPT-5.1 and GPT-5.6 Sol: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.

Model compare
GPT-5.1
GPT-5.6 Sol
Overall leaderContenderLeading
Weighted overall score29.3 pts70.7 pts
Benchmark category leads1 categories5 categories
Operational advantagesAverage speed, First-token latency, Free providers, Provider coverageCheapest input price
Context window400K tokens1.1M tokens
Max output128K tokens128K tokens
Modalities

Input

ImageTextFile

Output

Text

Input

FileImageText

Output

Text
Features
Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning
Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning

The overall result weights benchmark capability categories at 80% and price, API speed/latency, and availability at 20%. Recent test volume does not affect the winner, and missing benchmark categories are excluded.

Model metadata

Model compare
GPT-5.1
GPT-5.6 Sol
DeveloperOpenAIOpenAI
ReleasedNov 2025Jul 2026
ParametersNo dataNo data
TokenizerGPTGPT
Knowledge cutoffNo data2026-02-16
OpenRouter IDopenai/gpt-5.1openai/gpt-5.6-sol
ReferencesNo dataNo data

When to choose each model

This report only uses LMSpeed data for GPT-5.1 and GPT-5.6 Sol: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.

GPT-5.1

GPT-5.1 is stronger in benchmark categories (Instruction following) and operational dimensions (Average speed, First-token latency, Free providers, Provider coverage).

GPT-5.6 Sol

GPT-5.6 Sol is stronger in benchmark categories (Agents, Coding, Reasoning, Knowledge, Math) and operational dimensions (Cheapest input price).

Benchmark score comparison

Third-party benchmark profile synced into LMSpeed; only metrics available for both models are shown.

Category performance

Compare benchmark category scores on a 0-100 scale. Select a category to inspect the gap.

Model A coverage
6 / 8
Model B coverage
7 / 8
Shared
6 shared categories

Avg. score

GPT-5.1

51.9

Avg. score

GPT-5.6 Sol

61

Agents

GPT-5.6 Sol leads by 19.4

GPT-5.147.7
GPT-5.6 Sol67.1

Coding

GPT-5.6 Sol leads by 12.7

GPT-5.149.1
GPT-5.6 Sol61.8

Reasoning

GPT-5.6 Sol leads by 7.2

GPT-5.154
GPT-5.6 Sol61.2

Knowledge

GPT-5.6 Sol leads by 4.2

GPT-5.153
GPT-5.6 Sol57.2

Math

GPT-5.6 Sol leads by 13.0

GPT-5.154
GPT-5.6 Sol67

Multilingual

No data

GPT-5.1-
GPT-5.6 Sol-

Multimodal

GPT-5.6 Sol

GPT-5.1-
GPT-5.6 Sol59.5

Instruction following

GPT-5.1 leads by 0.1

GPT-5.153.5
GPT-5.6 Sol53.4

Professional benchmark details

Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.

Aggregatereported

BenchLM overall score

SourceGPT-5.1

GPT-5.1

56.0

Rank #56/100 · confidence 1 · eval date 2025-11-13

+27.0

GPT-5.6 Sol

winner

83.0

Rank #2/100 · confidence 3 · eval date 2026-07-09

Pricingverified

Input price

SourceGPT-5.1 (high)

GPT-5.1

winner

$1.25/M

Rank #118/179 · confidence 4

+$2.75/M

GPT-5.6 Sol

$4.00/M

Rank #160/179 · confidence 4

Pricingverified

Blended price

SourceGPT-5.1 (high)

GPT-5.1

winner

$3.44/M

Rank #134/179 · confidence 4

+$4.56/M

GPT-5.6 Sol

$8.00/M

Rank #162/179 · confidence 4

Pricingverified

Output price

SourceGPT-5.1 (high)

GPT-5.1

winner

$10.00/M

Rank #137/179 · confidence 4

+$10.00/M

GPT-5.6 Sol

$20.00/M

Rank #162/179 · confidence 4

Reasoningreported

CritPt

SourceGPT-5.1

GPT-5.1

4.9

Rank #43/83 · confidence 1 · eval date 2025-11-13

+27.4

GPT-5.6 Sol

winner

32.3

Rank #1/83 · confidence 3 · eval date 2026-07-09

Reasoningverified

GPQA

SourceGPT-5.1 (high)

GPT-5.1

87.3%

Rank #47/211 · confidence 4

+5.5%

GPT-5.6 Sol

winner

92.8%

Rank #11/211 · confidence 4

Reasoningverified

HLE

SourceGPT-5.1 (high)

GPT-5.1

28.5%

Rank #55/208 · confidence 4

+17.5%

GPT-5.6 Sol

winner

46.0%

Rank #11/208 · confidence 4

Reasoningreported

AA-LCR

SourceGPT-5.1

GPT-5.1

76.7

Rank #19/100 · confidence 1 · eval date 2025-11-13

+1.0

GPT-5.6 Sol

winner

77.7

Rank #15/100 · confidence 3 · eval date 2026-07-09

Codingreported

AA Coding Index

SourceGPT-5.1

GPT-5.1

49.4

Rank #42/70 · confidence 1 · eval date 2025-11-13

+28.0

GPT-5.6 Sol

winner

77.4

Rank #2/70 · confidence 3 · eval date 2026-07-09

Codingverified

SciCode

SourceGPT-5.1 (high)

GPT-5.1

43.3%

Rank #55/204 · confidence 4

+13.6%

GPT-5.6 Sol

winner

56.9%

Rank #5/204 · confidence 4

Codingreported

AA-SciCode

SourceGPT-5.1

GPT-5.1

43.3

Rank #55/108 · confidence 1 · eval date 2025-11-13

+12.8

GPT-5.6 Sol

winner

56.1

Rank #8/108 · confidence 3 · eval date 2026-07-09

Mathreported

BenchLM Math score

SourceGPT-5.1

GPT-5.1

49.7

Rank #36/62 · confidence 1 · eval date 2025-11-13

+47.2

GPT-5.6 Sol

winner

96.9

Rank #1/62 · confidence 3 · eval date 2026-07-09

Mathreported

FrontierMath v2 (Tier 4)

SourceGPT-5.1

GPT-5.1

12.5

Rank #16/35 · confidence 1 · eval date 2025-11-13

+70.5

GPT-5.6 Sol

winner

83.0

Rank #1/35 · confidence 3 · eval date 2026-07-09

Mathreported

FrontierMath v2 (Tiers 1-3)

SourceGPT-5.1

GPT-5.1

31.0

Rank #19/47 · confidence 1 · eval date 2025-11-13

+58.0

GPT-5.6 Sol

winner

89.0

Rank #1/47 · confidence 3 · eval date 2026-07-09

Knowledgereported

AA-GPQA Diamond

SourceGPT-5.1

GPT-5.1

87.3

Rank #44/108 · confidence 1 · eval date 2025-11-13

+6.8

GPT-5.6 Sol

winner

94.1

Rank #3/108 · confidence 3 · eval date 2026-07-09

Knowledgereported

AA-HLE

SourceGPT-5.1

GPT-5.1

28.5

Rank #47/108 · confidence 1 · eval date 2025-11-13

+21.0

GPT-5.6 Sol

winner

49.5

Rank #3/108 · confidence 3 · eval date 2026-07-09

Knowledgereported

AA-Omniscience Accuracy

SourceGPT-5.1

GPT-5.1

37.7

Rank #39/101 · confidence 1 · eval date 2025-11-13

+21.7

GPT-5.6 Sol

winner

59.4

Rank #3/101 · confidence 3 · eval date 2026-07-09

Knowledgereported

Artificial Analysis Intelligence Index

SourceGPT-5.1

GPT-5.1

37.5

Rank #52/111 · confidence 1 · eval date 2025-11-13

+21.4

GPT-5.6 Sol

winner

58.9

Rank #5/111 · confidence 3 · eval date 2026-07-09

Knowledgereported

AA-Omniscience Hallucination Rate

SourceGPT-5.1

GPT-5.1

51.9

Rank #72/101 · confidence 1 · eval date 2025-11-13

+40.3

GPT-5.6 Sol

winner

92.2

Rank #12/101 · confidence 3 · eval date 2026-07-09

Knowledgereported

AA-Omniscience Index

SourceGPT-5.1

GPT-5.1

5.4

Rank #24/40 · confidence 1 · eval date 2025-11-13

+16.6

GPT-5.6 Sol

winner

22.0

Rank #12/40 · confidence 3 · eval date 2026-07-09

Multimodalreported

AA-MMMU-Pro

SourceGPT-5.1

GPT-5.1

75.5

Rank #28/65 · confidence 1 · eval date 2025-11-13

+7.9

GPT-5.6 Sol

winner

83.4

Rank #4/65 · confidence 3 · eval date 2026-07-09

Instruction followingreported

AA-IFBench

SourceGPT-5.1

GPT-5.1

winner

72.9

Rank #28/84 · confidence 1 · eval date 2025-11-13

+0.2

GPT-5.6 Sol

72.7

Rank #29/84 · confidence 3 · eval date 2026-07-09

Agentsreported

AA Agentic Index

SourceGPT-5.1

GPT-5.1

21.6

Rank #47/65 · confidence 1 · eval date 2025-11-13

+36.2

GPT-5.6 Sol

winner

57.8

Rank #4/65 · confidence 3 · eval date 2026-07-09

Agentsreported

GDPval-AA

SourceGPT-5.1

GPT-5.1

24.6

Rank #46/61 · confidence 1 · eval date 2025-11-13

+36.5

GPT-5.6 Sol

winner

61.1

Rank #5/61 · confidence 3 · eval date 2026-07-09

Agentsreported

GDPval-AA

SourceGPT-5.1

GPT-5.1

993.0

Rank #46/66 · confidence 1 · eval date 2025-11-13

+742.0

GPT-5.6 Sol

winner

1735.0

Rank #5/66 · confidence 3 · eval date 2026-07-09

Agentsreported

τ²-bench results

SourceGPT-5.1

GPT-5.1

81.9

Rank #53/82 · confidence 1 · eval date 2025-11-13

+3.2

GPT-5.6 Sol

winner

85.1

Rank #44/82 · confidence 3 · eval date 2026-07-09

API audit comparison

Latest completed audits from shared providers, with four safety and integrity score groups plus report links.

Provider
GPT-5.1
GPT-5.6 Sol
No completed audits are available from shared providers yet.

Provider examples

Speed aggregates and input/output pricing share each provider row for real API selection and migration cost checks.

Provider
GPT-5.1
GPT-5.6 Sol
BUZZ10 tests

GPT-5.1

speed / latency

137 tok/s / 3299ms

input / output

No data

GPT-5.6 Sol

speed / latency

N/A / N/A

input / output

No data

YUNWU API10 tests

GPT-5.1

speed / latency

N/A / N/A

input / output

No data

GPT-5.6 Sol

speed / latency

53 tok/s / 2164ms

input / output

No data

N1N5 tests

GPT-5.1

speed / latency

96 tok/s / 1862ms

input / output

No data

GPT-5.6 Sol

speed / latency

N/A / N/A

input / output

No data

XShuLab Sub2API5 tests

GPT-5.1

speed / latency

152 tok/s / 936ms

input / output

No data

GPT-5.6 Sol

speed / latency

N/A / N/A

input / output

No data

星辰·AI5 tests

GPT-5.1

speed / latency

N/A / N/A

input / output

No data

GPT-5.6 Sol

speed / latency

37 tok/s / 5320ms

input / output

No data

APIMart

GPT-5.1

gpt-5.1-2025-11-13

speed / latency

No data

input / output

$0.959/M/$7.67/M

GPT-5.6 Sol

gpt-5.6-sol

speed / latency

No data

input / output

$0/M/$0/M

兔子API

GPT-5.1

gpt-5.1-chat-latest

speed / latency

No data

input / output

$0/request

GPT-5.6 Sol

gpt-5.6-sol

speed / latency

No data

input / output

$0/request

初叶🍂Furry API

GPT-5.1

gpt-5-1

speed / latency

No data

input / output

$0/request

GPT-5.6 Sol

gpt-5.6-sol

speed / latency

No data

input / output

$0.200/request

Yun API

GPT-5.1

gpt-5.1

speed / latency

No data

input / output

$0.0027/request

GPT-5.6 Sol

gpt-5.6-sol-medium

speed / latency

No data

input / output

$0.171/M/$1.03/M

KFCV50

GPT-5.1

gpt-5.1

speed / latency

No data

input / output

$0.0068/request

GPT-5.6 Sol

gpt-5.6-sol

speed / latency

No data

input / output

$0.068/M/$0.411/M

FAQ

Weighted outcome: GPT-5.6 Sol. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.

Why is this comparison indexable?
It has 6 verifiable comparison points, and both models have pricing or benchmark data.
Are missing metrics invented?
No. Metrics without LMSpeed data are omitted from this report.

Rankings are based on community-submitted tests and periodic health probes. Advisory only, not official data.