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- Apr 16, 202595% CONFIDENCEfrom help.openai.com
OpenAI o3 and o4-mini Released
- OpenAI released o3, called its most advanced reasoning model, and o4-mini, a cost-efficient reasoning model, on 16 April 2025, with o4-mini-high, to ChatGPT Pro, Plus and Team users[1][2][3]
- OpenAI planned o3-pro for ChatGPT Pro in the coming weeks (released 10 June 2025); Altman indicated o3 and o4-mini might be the last stand-alone reasoning models before GPT-5[1][2][3]
- o3 was originally announced on 20 December 2024; OpenAI later announced its ChatGPT retirement for 26 August 2026, with the API unaffected[1][2]
Notable features
- They were the first models able to 'think with images' (whiteboard sketches, zooming and rotating while reasoning) and can use ChatGPT tools including web browsing, Python and image generation[3]
- OpenAI says o3 set new state-of-the-art results on Codeforces, SWE-bench and MMMU and made 20 percent fewer major errors than o1 on difficult real-world tasks in external expert evaluations; both models were trained with reinforcement learning to reason about when and how to use tools[4]
- o4-mini was the best-performing benchmarked model on AIME 2024 and 2025, scoring 99.5% pass@1 on AIME 2025 with a Python interpreter (o3 98.4%), and supports significantly higher usage limits than o3[4]
- They were also added to the Chat Completions and Responses APIs: o3 at $10 per million input and $40 output tokens, o4-mini at $1.10 and $4.40[3]
- On SWE-bench Verified TechCrunch reports o3 at 69.1% and o4-mini at 68.1%, against o3-mini at 49.3% and Claude 3.7 Sonnet at 62.3%[3]
References 488% CONFIDENCE
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- [1]95%OpenAI Model Release Notes: OpenAI o3 and o4-mini (April 16, 2025)help.openai.com· Posted Sep 19, 2026· Starts Apr 16, 2025· 44% of score
OpenAI's own model release notes date this entry April 16, 2025
- [2]80%OpenAI o3 - Wikipediaen.wikipedia.org· Added Sep 19, 2026· 44% of score
States OpenAI[1] released o3 and o4-mini on April 16, 2025.
- [3]90%OpenAI launches a pair of AI reasoning models, o3 and o4-minitechcrunch.com· Published Apr 16, 2025· 6% of score
TechCrunch report dated April 16, 2025 on the o3 and o4-mini launch.
- [4]88%Introducing OpenAI o3 and o4-mini | OpenAI (Wayback Machine copy)web.archive.org· Published Apr 16, 2025· 6% of score
Archived copy of OpenAI's[1] o3 and o4-mini announcement, which says o3 "sets a new SOTA on benchmarks including Codeforces, SWE-bench ... and MMMU", makes "20 percent fewer major errors than OpenAI o1", and o4-mini "achieves 99.5% pass@1" on AIME 2025 with Python.
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