All models

OpenAIUnited States· released Apr 2026

GPT-5.5 Pro

Provisional: 6 comparable tests so far. Ranked once it reaches 6 across 3 counting categories.

OpenAI, United States. One of 26 models from this lab on the Index.

Third-party publishedLow confidence (thin coverage)

Snapshot September 8, 2026

OpenCharts Index

93.9

Provisional: not enough comparable tests or counting categories to rank yet · 6 comparable tests · 1 counting categories

Drop any single test and the Index lands between 92.5 and 95.5.

HARD SET

Needs more results (3 of 8 so far)

Averaging 87.5 on the 3 it has; the score opens at 4 of 8.

Distance to today's frontier on the hardest tests. Not a measure of intelligence.

What it's known for

GPT-5.5 Pro, in 6 results.

Strongest in reasoning (93.9). Its widest gap is on FrontierMath Tier 4, 20.0% behind the best published result. No comparable results yet in knowledge, coding, agentic, multimodal, human preference and long context. Between 5% and 10% behind the best published results, on average.

Strongest category

Reasoning

Hard, novel problems: graduate science, abstract puzzles, expert exams.

93.9

Mean of 4 of the category's 6 comparable tests. Counts toward the Index.

Best single result

ARC-AGI-1

Solve the original Abstraction and Reasoning Corpus: small grids, a handful of examples, one hidden rule.

96.5%

98.0% of the best (98.5%) · #7 of 51.

The first ARC set is close to saturated at the frontier, so it now shows whether smaller models can generalize at all.

Where it trails

FrontierMath Tier 4

Solve the hardest FrontierMath tier: problems that take expert mathematicians days.

78.0%

20.0% behind the best published result (97.6%) · #6 of 51.

The deepest end of the set. Progress here signals genuinely new capability.

Not measured yet

No comparable result yet in these 6 categories. A blank is a blank, never a zero, and it does not lower the Index.

  • Knowledge
  • Coding
  • Agentic
  • Multimodal
  • Human preference
  • Long context

Covered, but not averaged into the Index:

  • Math2 of 5 tests · needs 3 · mean 86.8
Every score, with its source

See it at work

What GPT-5.5 Pro was asked to do, and how it did.

Every test it has taken, by category, with the kind of task it faced, who produced the number and where the result landed against the best published one. The examples are original and illustrative, never items from the datasets themselves.

Reasoning · mean 93.9 across 4 comparable tests · counts toward the Index

ARC-AGI-1Leaderboard

Solve the original Abstraction and Reasoning Corpus: small grids, a handful of examples, one hidden rule.

96.5%

98.0% of the best (98.5%)
#7 of 51 · n = 100

high

Close to saturated at the frontier; scores depend on the compute budget a lab chose.

Source: ARC Prize Foundation
CritPtLeaderboard

Solve an unpublished research-level physics problem to a numeric or symbolic answer checked by an official server.

30.6%

94.6% of the best (32.3%)
#4 of 78

xhigh

Source: CritPt / Artificial Analysis
SimpleBenchLeaderboard

Answer everyday trick questions about the physical and social world that most people find easy.

76.9%

93.9% of the best (81.9%)
#4 of 46

Source: SimpleBench / LM Council
ARC-AGI-2Hard setLeaderboard

Infer the hidden rule from a few input and output grid pairs, then apply it to a new grid.

84.6%

89.0% of the best (95.0%)
#7 of 51 · n = 120

high

Scores depend on the compute budget a lab chose; ARC Prize publishes cost per task beside every score and this ranking does not.

Source: ARC Prize Foundation

Every result is read against the best published one on its test: percent scores as a share of the best above chance, Arena ratings as the expected win rate against the board leader, open-ended values on a log scale. Sitting a harder exam never lowers a model. Every number links to the publisher that produced it.

Head to head

GPT-5.5 Pro against whoever you pick.

Choose a rival. Every counted test both have taken appears side by side as a share of the best published result on that test, with the category means above. A win is a higher share; a gap under 2 points is a tie, because one item on a 45-problem exam is 2.2 points and publishers' own standard errors are of that order.

GPT-5.5 Pro

provisional·Index 93.9A

0 : 5

wins · 0 ties · 5 shared

GPT-6 Astra

#1·Index 99.0A+

GPT-6 Astra comes out ahead on 5 of the 5 tests both have taken.

Category means

  • Reasoning

    93.9
    99.6
  • Knowledge

    100.0
  • Coding

    97.7
  • Math

    86.8
    99.8
  • Agentic

    98.5

Shared tests · biggest gaps first

Bars are distances to the best published result on each test (percent scores above chance, Arena ratings as win rate against the leader, open-ended values on a log scale). Raw values as the publishers report them.

Open GPT-6 Astra

Scores

Every test, every source

The best published run per benchmark, the raw value as the publisher reports it, who produced the number, how close it comes to the best published result on that test, and where the model sits among every model scored on it. Percent scores are read above chance, Arena ratings as a win rate against the board leader, open-ended values on a log scale. A test with too few models to compare against is shown but not counted.

Category means

  • Reasoning93.9 · 4/6
  • Knowledge
  • Coding
  • Math86.8 · 2/5
  • Agentic
  • Multimodal
  • Human preference
  • Long context

Mean · tests taken of the category's comparable tests. A faded category either rests on fewer than half of them or is a single-test category (marked “beside”), which is shown next to the Index and never averaged into it.

ARC-AGI-2LeaderboardReasoning

84.6%

89.0% of the best (95.0%)
84th percentile of 51 · n = 120

high

Source: Epoch AI — AI Benchmarking Hub
ARC-AGI-1LeaderboardReasoning

96.5%

98.0% of the best (98.5%)
86th percentile of 51 · n = 100

high

Source: Epoch AI — AI Benchmarking Hub
SimpleBenchLeaderboardReasoning

76.9%

93.9% of the best (81.9%)
93th percentile of 46

Source: Epoch AI — AI Benchmarking Hub
CritPtLeaderboardReasoning

30.6%

94.6% of the best (32.3%)
96th percentile of 78

xhigh

Source: Epoch AI — AI Benchmarking Hub

87.7%

93.6% of the best (93.7%)
95th percentile of 61 · n = 290

xhigh

Source: Epoch AI — AI Benchmarking Hub
FrontierMath Tier 4Epoch-runMath

78.0%

80.0% of the best (97.6%)
90th percentile of 51 · n = 48

xhigh

Source: Epoch AI — AI Benchmarking Hub

Top of the leaderboard

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