OpenAI launches o3, its most advanced reasoning model, and o4-mini, a lower cost alternative that still delivers “impressive results”, for ChatGPT paid users

ChatGPT Plus users can begin using both new models starting today. — A mere two days after announcing GPT-4.1, OpenAI is releasing not one but two new models.

Engadget 2025-04-17 Igor Bonifacic

Context & Ripple Effects

OpenAI had already broadened access to reasoning with o3-mini for free ChatGPT users, while earlier coverage framed o-series models as trading cost and performance for stronger reasoning. This release moves the paid tier’s frontier forward with both a flagship and a lower-cost option.

The launch also follows closely after GPT-4.1’s announcement, reinforcing a product cadence in which ChatGPT users are offered multiple model classes rather than a single universal default.

First-order effects

ChatGPT Plus users gain immediate access to o3 for OpenAI’s highest-positioned reasoning capability and o4-mini as a lower-cost alternative.
OpenAI expands its paid-user model lineup, making the choice between maximum reasoning performance and lower-cost performance more explicit.

Second-order effects

The paired release gives OpenAI a way to route different paid-user tasks toward different cost-performance profiles, rather than treating reasoning as one premium offering.
It increases pressure on ChatGPT’s own product experience to make model selection legible: users now have more capability options arriving alongside GPT-4.1’s subsequent ChatGPT rollout.

Third-order effects

If this release pattern persists, reasoning models may become a tiered product category defined by cost per useful task, not simply a sequence of larger flagship models.
The longer-term differentiator may shift toward how well AI platforms package and steer users among specialized models, with pricing and access tiers becoming part of the capability proposition.

The trend: This is another step in the unbundling of frontier AI into a portfolio of reasoning models optimized for different performance and cost thresholds.

Discussion

@pixeltrix Andrew White on bluesky
OpenAI has got more heads than Worzel Gummidge at this point [embedded post]
@quinnypig.com Corey Quinn on bluesky
The OpenAI product line is like my homelab, in that I've named the nodes server1, server2, 5, 👺, #!, ,, m-as-in-mancy, the EICAR test string, and a sound at a pitch only dogs can hear. [embedded post]
@natolambert Nathan Lambert on bluesky
TLDR on o3 and o4-mini: incremental. pace of progress still really high, no dramatic changes in performance or shocking new features. Pressure to ship fast across the industry has never been higher.
@gdb Greg Brockman on x
Just released o3 and o4-mini! These models feel incredibly smart. We've heard from top scientists that they produce useful novel ideas. Excited to see their positive impact on people's daily lives and humanity's hardest problems! https://openai.com/...
@emollick Ethan Mollick on x
A potential issue with o3 is that it thinks it is using tools even when it does not, leading to some hallucinations where it assumes work that was implied in the reasoning chain was actually done. You should double check the reasoning trace for complex work to see what it did.
@sama Sam Altman on x
o3 and o4-mini are out! they are very capable. o4-mini is a ridiculously good deal for the price. they can use and combine every tool within chatgpt. multimodal understanding is particularly impressive.
@sama Sam Altman on x
we expect to release o3-pro to the pro tier in a few weeks
@snsf Srinivas Narayanan on x
o3 and o4-mini are here. They set new highs on science, math, coding and reasoning benchmarks. Personally, it has been fun for me to see o3 ace many physics olympiad type problems that previous models struggled on. Their ability to use tools - search, analysis with python,
@csvoss Chelsea Sierra Voss on x
not to perpetually shill, but... Tyler's right, o3 is pretty remarkable. a step change in both intelligence and UX. o1 felt like my peer who can keep up and think together with me, but o3 is my intimidatingly smart friend whose PhD was in whatever I happen to be asking about 😳
@_adiganesh Adi Ganesh on x
o3 and o4-mini are really intelligent models. I love the way o3 can answer complex queries about research papers. For example, I uploaded a PDF of “Cell type signatures in cell-free DNA fragmentation profiles reveal disease biology” from Nature Communications 2024 [image]
@markchen90 Mark Chen on x
We launched o3 and o4-mini today! Reasoning models are so much more powerful once they learn how to use tools end-to-end. Some of the biggest lifts are coming in multimodal domains like visual perception (see how it solves a maze in our blogpost: https://openai.com/... 🤯)
@carmenleelau Carmen on x
I'm obsessed with o3. It's way better than the previous models. It just helped me resolve a psychological/emotional problem I've been dealing with for years in like 3 back-and-forths (one that wasn't socially acceptable to share, and those I shared it with didn't/couldn't help)
@slow_developer Haider on x
finally, gemini 2.5 pro has been dethroned after a long time o3 beats gemini 2.5 on LiveBench, and it looks like both models ain't going anywhere at least in coding: - o3 score 73 - o4-mini score 74 - gemini 2.5 score 58 also, o4-mini is 2x cheaper than gemini 2.5 pro [image]
@lukeprog Luke Muehlhauser on x
Tyler Cowen: “I've seen enough, I'm calling it, o3 is AGI” Meanwhile, o3 in response to the first prompt I give it: [image]
@mparakhin Mikhail Parakhin on x
O3 continues to show potential, but without the Pro version still remains a toy for my usage scenarios.
@johnohallman John Hallman on x
When o3 finished training and we got to try it out, I felt for the first time tempted to call a model AGI. Still not perfect, but this model will beat me, you, and 99% of humans on 99% of intelligence assessments. One can start to see the light at the end of the tunnel
@smokeawayyy @smokeawayyy on x
This is the first release that feels like a bit of deceleration. It's not the o3 that scored 87.5% on ARC-AGI. o4-mini outperforms o4-mini-high on some benchmarks. Not saying there's a wall, but there might actually be a chance for the competition to close the gap on OpenAI.
@simonw Simon Willison on x
Interesting OpenAI-insider tip on Hacker News: “o4-mini is actually a considerably better vision model than o3, despite the benchmarks” https://news.ycombinator.com/ ... [image]
@azure @azure on x
OpenAI o3 and o4-mini models are now available on Azure OpenAI Service. Key features include: 🔹 Multiple APIs support 🔹 Reasoning summary 🔹 Multimodality 🔹 Full tools support Read more: https://azure.microsoft.com/ ... #AzureAI
@garymarcus Gary Marcus on x
Tyler Cowen @tylercowen is claiming (without giving a real definition) that o3 is AGI. I guarantee his claim won't stand the test of time, and in 5 years people will laugh at the idea that o3 was AGI. As Mollick (and I) have noted o3 is just not going to be systematically
@polynoamial Noam Brown on x
We did not “solve math”. For example, our models are still not great at writing proofs. o3 and o4-mini are nowhere close to getting International Mathematics Olympiad gold medals.
@kimmonismus @kimmonismus on x
I said it in December 2024 and I say it again: o3 is imho AGI and I agree with Tyler Cowen. There is no standard definition of what AGI is. For me, the definition of Google DeepMind speaks more to the definition of superintelligence. And actually it is also silly to argue abou…
@natolambert Nathan Lambert on x
Models I'm using, roughly, these days, ~monthly: * ChatGPT, 4.5 ~ o1pro > 4o: ~90% * Gemini 2.5 Pro: ~10% * Claude 3.7: <1% * Grok: <1% * Random open models: <1% Will keep posting these every so often. I expect to slot o3 in for a lot. 4.5 is general queries (talking about
@natolambert Nathan Lambert on x
TLDR on o3 and o4-mini: incremental. pace of progress still really high, no dramatic changes in performance or shocking new features. Pressure to ship fast across the industry has never been higher.
@tunguz Bojan Tunguz on x
I just got fired from OpenAI. I was on the marketing team, in charge of naming our products. If you know someone who is looking for an experienced marketer with strong autistic naming tendencies, please feel free to reach out. [image]
@emollick Ethan Mollick on x
After using them both, I think that Gemini 2.5 & o3 are in a similar sort of range (with the important caveat that more testing is needed for agentic capabilities) Each has its own quirks & you will likely prefer one to another, but there is a gap between them & other models
@miles_brundage Miles Brundage on x
I don't love the term AGI but o3 is crazy, o3 pro will be crazier, o5-pro will be super duper crazy, etc. There is no single right definition/threshold for “AI that matters a lot.” But for all reasonable ones, we've exceeded it or will exceed it in the next few years.
@gdb Greg Brockman on x
Just released o3 and o4-mini! These models feel incredibly smart. We've heard from top scientists that they produce useful novel ideas. Excited to see their positive impact on people's daily lives and humanity's hardest problems!
@emollick Ethan Mollick on x
Interesting argument from @tylercowen. Is o3 good enough to be AGI? The counter argument might force us to wait until ASI, because only then will an AI definitively outperform all humans at all tasks. In the meantime we have a Jagged AGI, with subhuman & superhuman abilities. [im…
@flavioad Flavio Adamo on x
o3 and o4-mini have absolutely NAILED the vibe check ✅ This is best result so far! [video]
@aidan_mclau Aidan McLaughlin on x
ignore literally all the benchmarks the biggest o3 feature is tool use ofc it's smart, but it's also just way more useful >deep research quality in 30 seconds >debugs by googling docs and checking stackoverflow >writes whole python scripts in its CoT for fermi estimates
@bindureddy Bindu Reddy on x
When it rains, it pours! o3 and o4-mini available worldwide o4-mini pricing is excellent 1M input - $1.10 1M output - $4.40 Both seem like good models. Will post on LiveBench and ChatLLM in a couple of hours
@danshipper Dan Shipper on x
one good way to think about o3: it's deep research-lite someone from openai said this to me and it's totally true. it's like deep research for everything, but it takes 30 seconds to 5 minutes instead of taking 20 it did a fantastic job of helping me prep for my @kevin2kelly [imag…
@polynoamial Noam Brown on x
Today, we're releasing @OpenAI o3/o4-mini. The eval numbers are SOTA (2700 Elo is among the top 200 competition coders) But what I'm most excited about is the stuff we can't benchmark. I expect o3/o4-mini will aid scientists in their research and I'm excited to see what they do! …
@garymarcus Gary Marcus on x
Reposting (and standing by) these predictions from December before the initial o3 announcement:
@emollick Ethan Mollick on x
I had early access, o3 is an impressive model, seems very capable. Some fun examples: 1) Cracked a business case I use in my class 2) Creating some SVGs (images created by code alone) 3) Writing a constrained story of two interlocking gyres 4) Hard science fiction space battle. […
@alexandr_wang Alexandr Wang on x
🚨 @OpenAI has launched o3 and o4-mini! 🎉 o3 is absolutely dominating the SEAL leaderboard with #1 rankings in: 🥇: HLE 🥇: Multichallenge (multi-turn) 🥇: MASK (honesty under pressure) 🥇: ENIGMA (puzzle solving) Congrats @sama @markchen90 & team 🔗: https://scale.com/... [image]
r/mlscaling r on reddit
Introducing OpenAI o3 and o4-mini
r/LocalLLaMA r on reddit
OpenAI Introducing OpenAI o3 and o4-mini
r/OpenAI r on reddit
Introducing o3 and o4-mini
@timkellogg.me Tim Kellogg on bluesky
hands down, the biggest news is codex — open source Claude Code, but with OpenAI models — no MCP or Azure support yet, although it is open source, and PRs emerged 30 min after the live stream ended — github.com/openai/codex
@sungkim Sung Kim on bluesky
OpenAI releases Codex CLI — Anthropic releases Claude Code. — Claude Code becomes popular. — OpenAI copies Claude Code. — OpenAI cannot release its copy without facing significant criticism, so it open-sources it. — github.com/openai/codex
@alice.mosphere.at Alice on bluesky
praise be, they made a claude code without claude (claude does not have the mandate of heaven) — can't wait to play with this — i do wonder if a third-party agent with gemini 2.5 pro is still the best though. we'll see — github.com/openai/codex [image]
@sama Sam Altman on x
o3 and o4-mini are super good at coding, so we are releasing a new product, Codex CLI, to make them easier to use. this is a coding agent that runs on your computer. it is fully open source and available today; we expect it to rapidly improve.
@simonw Simon Willison on x
Wrote some notes on OpenAI codex, their new open CLI “agent” tool for writing and iterating on code. Since it's open source (Apache 2) the workings are available, including an interesting system prompt and a macOS sandbox using the sandbox-exec mechanism https://simonwillison.net…
@iannuttall Ian Nuttall on x
openai literally just threw down the gauntlet to anthropic by launching an open source coding agent alongside o3 and o4-mini [image]
@mjbommar Michael Bommarito on x
for once, i will give true props to openai - making the codex cli fully open under Apache-2.0 is the right thing to do, unlike what anthropic did with claude code (including the gh dmca after it was reverse engineer/deobfuscated). to be clear, i still don't trust the incentives b…
r/LocalLLaMA r on reddit
OpenAI introduces codex: a lightweight coding agent that runs in your terminal
r/ChatGPTCoding r on reddit
OpenAI quietly releases their own terminal based coding assistant! [Codex]

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