Chat model

GPT-6.1 Sol

high reasoning · 16 questions per request

97.8% of the 2,198 questions right (97.1% to 98.3%, 95% interval). Back to the leaderboard.

Which decision model can go first in front of it? See the Routing tab.

How we called it

Kind: Chat model
Access: Codex CLI, ChatGPT subscription
Paid as: Subscription
Model ID: gpt-6.1-sol
Note: It stopped after 1,792 answers when the service reported the model at capacity, and was resumed for the other 406 questions; the usage and cost of the failed request are unknown.
Confidence from: Written estimate
Run: 276, 28 October 2026

Settings

Reasoning: high
Request format: 16 questions per request
Requests at once: 1
Temperature: not recorded
Harness seed: 0
Harness commit: 0fbd97b0899d
Prompt version: 254597b8be16

Reasoning effort levels (OpenAI's model page, read 28 October 2026): low, medium (default), high, xhigh, max. Top level: max. This run: high.

Results

Questions	Accuracy	95% interval	Right
All questions	97.8%	97.1% to 98.3%	2,149 of 2,198
Reading	96.5%	94.8% to 97.7%	633 of 656
Grammar	98.3%	97.5% to 98.8%	1,516 of 1,542

Comparison group: ab. Compare with another setup.

Accuracy by topic

Topic	Part	Accuracy	Right
Word and phrase meanings	Reading	97.7%	128 of 131
Sentence meanings	Reading	98.1%	151 of 154
How a writer explains and develops ideas	Reading	91.4%	64 of 70
Topic and main point of a paragraph	Reading	95.9%	94 of 98
How a paragraph fits together	Reading	95.3%	101 of 106
Details that support a paragraph’s main point	Reading	97.9%	95 of 97
Word types, such as nouns and verbs	Grammar	98.6%	138 of 140
Groups of words built around a noun	Grammar	98.5%	64 of 65
Verbs and their forms	Grammar	100.0%	91 of 91
Verb forms used like nouns or modifiers	Grammar	98.6%	71 of 72
Word endings and what they do	Grammar	98.7%	78 of 79
How words are built	Grammar	95.7%	66 of 69
The roles of words and phrases in a sentence	Grammar	97.9%	142 of 145
How verbs show who acts and who receives the action	Grammar	98.6%	73 of 74
Types of sentences	Grammar	98.8%	84 of 85
Questions combining several grammar topics	Grammar	98.6%	217 of 220
Sound patterns and changes	Grammar	98.7%	76 of 77
Spelling	Grammar	99.2%	132 of 133
Punctuation	Grammar	95.7%	112 of 117
Problems in sentence wording	Grammar	98.3%	172 of 175

Confidence

Answers kept at 99% or more: 1,826, of which 10 wrong (share right: 99.0% to 99.7%, 95% interval); 372 skipped, the model less than 99% sure
Calibration gap: 1.0 points
AUROC, all questions: 0.88 0.83 to 0.93
AUROC, reading: 0.95 0.89 to 0.98
AUROC, grammar: 0.82 0.74 to 0.90
Brier score: 0.019
Accuracy of its surest answers: most confident fifth: 100.0% right; most confident half: 99.6% right; most confident four fifths: 99.5% right
Typical score of a right answer: 99.0%
Typical score of a wrong answer: 96.0%

Repeats

Run 5 times on a sample of 200 questions.

Answers changed in 5 runs: 1 of 200
Same wrong answer in all 5: 3 of 200
Wrong in at least one run: 4 of 200
Accuracy in each run: 98.5%, 98.5%, 98.0%, 98.0%, 98.0%

Latency

Latency, median request: 24.7 s (this run)
Latency, 90th percentile: 70.3 s
Requests at once: 1
Throughput: 27.4 questions per minute of request time
Request time: 80.2 minutes, over the requests whose answers were kept

Latency: the time from sending one request to receiving its answer, measured from our computer, network and any retries within the request included. Request time: the time at least one request was in flight, over the requests whose answers were kept. It is not the run's elapsed time: it leaves out requests that failed and any pause before a run was resumed.

Cost

$ per 1,000 questions: $1.62
Whole run: $3.57
Basis: Subscription run priced as if we had used the API
Price: $2 input, $0.10 cached input, $2.50 cache writes, $10 output per 1M tokens (source, 2026-10-08)
Input tokens per question: 529
Output tokens per question: 74