Text / LLM / Model

OpenAI o3

Organisation
OpenAI
Family
o-series
Released
2025-04-16 (Date of the o3 and o4-mini System Card ('April 16, 2025'); matches API snapshot o3-2025-04-16)
Training cutoff
2024-06-01
Evidence
“Jun 01, 2024 knowledge cutoff”
developers.openai.com · website · Model page header · retrieved 2026-10-15
Checkpoints
o3-2025-04-16
Weights
Closed · proprietary
Links

Training data disclosure: Vague

Level determined for 13% of benchmark cells.

“OpenAI o3 and o4-mini were trained on diverse datasets, including information that is publicly available on the internet, information that we partner with third parties to access, and information that our users or human trainers and researchers provide”
cdn.openai.com · model card · Section 2 (Model Data and Training) · retrieved 2026-10-15

Other declared training data

Contamination analyses

Analyses that found benchmark test data in this model's training data, or in a corpus it uses.

Benchmark cells

Classic LLM benchmarks

Unknown MMLU (Measuring Massive Multitask Language Understanding) · training data not disclosed in enough detail

Unknown GSM8K (Grade School Math 8K) · training data not disclosed in enough detail

Unknown MATH (Mathematics Aptitude Test of Heuristics) · training data not disclosed in enough detail

Unknown HumanEval · training data not disclosed in enough detail

Unknown ARC-Challenge (AI2 Reasoning Challenge, Challenge Set) · training data not disclosed in enough detail

Unknown HellaSwag · training data not disclosed in enough detail

Unknown TruthfulQA · training data not disclosed in enough detail

Unknown WinoGrande · training data not disclosed in enough detail

Multimodal LLM benchmarks

Unknown MMMU (Massive Multi-discipline Multimodal Understanding and Reasoning) · training data not disclosed in enough detail

Unknown MMMU-Pro · training data not disclosed in enough detail

Unknown MathVista · training data not disclosed in enough detail

Unknown ChartQA · training data not disclosed in enough detail

Unknown DocVQA · training data not disclosed in enough detail

Unknown AI2D (AI2 Diagrams) · training data not disclosed in enough detail

Not seen CharXiv · its test items were published from 2024-06-26, after the model's stated training-data cutoff (2024-06-01)

Evidence (3)
“Jun 01, 2024 knowledge cutoff”
developers.openai.com · website · Model page header · retrieved 2026-10-15
“arXiv:2406.18521v1 [cs.CL] 26 Jun 2024”
arxiv.org · paper · arXiv v1 header · retrieved 2026-10-15
“we release all QA pairs for the validation set and keep the answers to the test set private to prevent data leakage.”
arxiv.org · paper · Section 3, footnote 4 · retrieved 2026-10-15

Recent LLM benchmarks

Unknown GPQA Diamond · training data not disclosed in enough detail

Unknown MMLU-Pro · training data not disclosed in enough detail

Unknown LiveCodeBench (code generation, release_v6) · training data not disclosed in enough detail

Test data seen SWE-bench Verified · a contamination analysis found test examples in the training data (Identifies the buggy file path from the issue text alone in up to 76% of SWE-bench Verified tasks, vs <53% on tasks from other repositories; the authors read it as possible memorisation/contamination.) [third-party study]

Evidence (2)
“on the file-path identification task, SoTA models like o3 [12] achieve up to 76% accuracy on SWE-Bench-Verified instances, despite lacking the contextual information that should be necessary for this task.”
arxiv.org third-party study· study · Section 1 · retrieved 2026-10-15
“Instead, accuracy is uniformly lower (<53%) than that in SWE-Bench Verified.”
arxiv.org third-party study· study · Section 4.1.2 · retrieved 2026-10-15

Unknown AIME 2024 · training data not disclosed in enough detail

Not seen AIME 2025 · its test items were published from 2025-02-06, after the model's stated training-data cutoff (2024-06-01)

Evidence (3)
“Jun 01, 2024 knowledge cutoff”
developers.openai.com · website · Model page header · retrieved 2026-10-15
“2025 AIME I problems and solutions. The test was held on Thursday, February 6, 2025.”
web.archive.org · website · retrieved 2026-10-15
“This year the AIME I will take place on February 6, 2025, while the alternate AIME II will take place on February 12, 2025.”
maa.org · website · retrieved 2026-10-15

Unknown MATH-500 · training data not disclosed in enough detail

Notes

o4-mini shares the system card but is a separate model (not included here). The card's 'contamination' discussion concerns browsing-based retrieval of answers during evaluation, not training data. Accepts image input: “Modalities Text Input and output Image Input only”

Sources