Chat model

GPT-6.1 Sol

low reasoning · 16 questions per request

96.7% of the 2,198 questions right (95.8% to 97.4%, 95% interval). Back to the leaderboard.

We also ran this setup at 1 question per request: GPT-6.1 Sol · low reasoning · 1 question per request.

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
Confidence from: Written estimate
Run: 124, 5 October 2026

Settings

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

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

Results

Questions	Accuracy	95% interval	Right
All questions	96.7%	95.8% to 97.4%	2,125 of 2,198
Reading	96.2%	94.4% to 97.4%	631 of 656
Grammar	96.9%	95.9% to 97.6%	1,494 of 1,542

Comparison group: cd. 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	93.4%	99 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	96.9%	63 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	94.2%	65 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	96.5%	82 of 85
Questions combining several grammar topics	Grammar	94.5%	208 of 220
Sound patterns and changes	Grammar	93.5%	72 of 77
Spelling	Grammar	97.7%	130 of 133
Punctuation	Grammar	94.0%	110 of 117
Problems in sentence wording	Grammar	97.7%	171 of 175

Confidence

Answers kept at 99% or more: 1,610, of which 13 wrong (share right: 98.6% to 99.5%, 95% interval); 588 skipped, the model less than 99% sure
Calibration gap: 1.5 points
AUROC, all questions: 0.86 0.81 to 0.90
AUROC, reading: 0.97 0.95 to 0.98
AUROC, grammar: 0.80 0.74 to 0.86
Brier score: 0.029
Accuracy of its surest answers: most confident fifth: 99.8% right; most confident half: 99.3% right; most confident four fifths: 98.9% right
Typical score of a right answer: 99.0%
Typical score of a wrong answer: 94.0%

Repeats

We did not repeat this setup.

Latency

Latency, median request: 13.3 s (this run)
Latency, 90th percentile: 24.6 s
Requests at once: 1
Throughput: 60.8 questions per minute of request time
Request time: 36.1 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: $1.13
Whole run: $2.48
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: 528
Output tokens per question: 25