GPT‑5.4 Mini and Nano
openai.com
openai.com
- Older GPT-5 Mini is about 55-60 tokens/s on API normally, 115-120 t/s when used with service_tier="priority" (2x cost).
- GPT-5.4 Mini averages about 180-190 t/s on API. Priority does nothing for it currently.
- GPT-5.4 Nano is at about 200 t/s.
To put this into perspective, Gemini 3 Flash is about 130 t/s on Gemini API and about 120 t/s on Vertex.
This is raw tokens/s for all models, it doesn't exclude reasoning tokens, but I ran models with none/minimal effort where supported.
And quick price comparisons:
- Claude: Opus 4.6 is $5/$25, Sonnet 4.6 is $3/$15, Haiku 4.5 is $1/$5
- GPT: 5.4 is $2.5/$15 ($5/$22.5 for >200K context), 5.4 Mini is $0.75/$4.5, 5.4 Nano is $0.2/$1.25
- Gemini: 3.1 Pro is $2/$12 ($3/$18 for >200K context), 3 Flash is $0.5/$3, 3.1 Flash Lite is $0.25/$1.5
This isn't usually an issue comparing models within the same provider, but it does mean cross-provider comparison using only tok/s is not apples-to-apples in terms of real-world performance.
For voice agents gpt-4.1 and gpt-4.1-mini seem to be the best low latency models when you need to handle bigger data more complex asks.
But they are a year old and trying to figure out if these new models(instant, chat, realtime, mini, nona, wtf) are a good upgrade is very frustrating. AFAICT they aren't; the TTFT latencies are too high.
gpt-5.4 is really good now also for tricky problems. Just for the unsolvable problems we take opus-4.6. Or if someone pays for it.
I've found Haiku to be a pretty fast at PP, but would be willing to investigate using another provider if they offer faster speeds.
The frontier models have become so good that it's getting almost impossible to notice meaningful differences between them.
Meanwhile, when a smaller / less powerful model releases a new version, the jump in quality is often massive, to the point where we can now use them 100% of the time in many cases.
And since they're also getting dramatically cheaper, it's becoming increasingly compelling to actually run these models in real-life applications.
Similarly gemini 3.1 flash lite got more expensive than gemini 2.5 flash lite.
What's the point of a crazy cheap model if it's shit ?
I code most of the time with haiku 4.5 because it's so good. It's cheaper for me than buying a 23€ subscription from Anthropic.
I often just think Gemini is terrible but then it turns out they silently changed the model on me
They're not really cheaper than the SOTA open models on third-party inference platforms, and they're generally dumber. I suppose they're still worth it if you must minimize latency for any given level of smarts, but not really otherwise.
5.4 mini seems to be a lot more wild/unstable, but with this instability it gets the right answer more often.
https://aibenchy.com/compare/openai-gpt-5-4-mini-medium/open...
So, every single time, the new model works most of the time?
Read it as: “You can use them full time in many cases”
They're incredibly slow (via official API or openrouter), but most of all they seem not to understand the instructions that I give them. I'm sure I'm _holding them wrong_, in the sense that I'm not tailoring my prompt for them, but most other models don't have problem with the exact same prompt.
Does anybody else have a similar experience?
That's really the story of my life. Trying to find a smart model with low latency.
Qwen 3.5 9b is almost smart enough and I assume I can run it on a 5090 with very low latency. Almost. So I am thinking I will fine tune it for my application a little.
Codex is an ice man. Every other model will have a thinking output that is meaningful and significant, that is walking through its assumptions. Codex outputs only a very basic idea of what it's thinking about, doesn't verbalize the problem or it's constraints at all.
Codex also is by far the most sycophantic model. I am a capable coder, have my charms, but every single direction change I suggest, codex is all: "that's a great idea, and we should totally go that [very different] direction", try as I might to get it to act like more of a peer.
Opus I think does a better job of working with me to figure out what to build, and understanding the problem more. But I find it still has a propensity for making somewhat weird suggestions. I can watch it talk itself into some weird ideas. Which at least I can stop and alter! But I find its less reliable at kicking out good technical work.
Codex is plenty fast in ChatGPT+. Speed is not the issue. I'm also used to GLM speeds. Having parallel work open, keeping an eye on multiple terminals is just a fact of life now; work needs to optimize itself (organizationally) for parallel workflows if it wants agentic productivity from us.
I have enormous respect for Codex, and think it (by signficiant measure) has the best ability to code. In some ways I think maybe some of the reason it's so good is because it's not trying to convey complex dimensional exploration into a understandable human thought sequence. But I resent how you just have to let it work, before you have a chance to talk with it and intervene. Even when discussing it is extremely extremely terse, and I find I have to ask it again and again and again to expand.
The one caveat i'll add, I've been dabbling elsewhere but mainly i use OpenCode and it's prompt is pretty extensive and may me part of why codex feels like an ice man to me. https://github.com/anomalyco/opencode/blob/dev/packages/open...
That’s not the model, that’s a personality setting you can change in the codex config file.
Set it to Pragmatic, and ask it (not command it) about your new direction in planning mode.
It will tell you if your idea is not good for the given project. It’s an excellent peer.
Yeah, I've actually heard many other people swear by the GPTs / Codex. I wonder what factors make one "click" with a model and not with another.
> Codex is an ice man.
That might be because OpenAI hides the actual reasoning traces, showing just a summary (if I understood correctly).
As an American, Claude feels much more natural to me, with the same overly-optimistic "move fast, break things" ethos that permeates our culture. It takes bigger swings (and misses) at harder-to-quantify concepts than Codex, cuts corners (not intentionally, but it feels like a human who's just moving too fast to see the forest for the trees in the moment), etc. Codex on the other hand feels more grounded, more prone to trying to aggregate blind spots, edge cases, and cover the request more thoroughly than Claude. It's far more pedantic and efficient, almost humorless. The dude also claimed that most of the Codex team is European while Claude team is American, and suggested that as an influence on why this might be.
Anyways, I've found that if I force Claude and Codex to talk to each other, I can get way better results and consistency by using Claude to generate fairly good plans from my detailed requests that it passes to Codex for review and amendment, Claude incorporates the feedback and implements the code, then Codex reviews the commit and patches anything Claude misses. Best of both worlds. YMMV
But joking aside, putting it like that I'd think I'd prefer the German/Codex way of doing things, yet I'm in camp Claude. But I've always worked better with teammates that balance my fastidiousness, so maybe that's my answer.
https://github.com/anthropics/claude-code/issues/31326#issue...
For agentic work, both Gemini 3.1 and Opus 4.6 passed the bar for me. I do prefer Opus because my SIs are tuned for that, and I don't want to rewrite them.
But ChatGPT models don't pass the bar. It seems to be trained to be conversational and role-playing. It "acts" like an agent, but it fails to keep the context to really complete the task. It's a bit tiring to always have to double check its work / results.
I prefer Claude models as well or open models for this reason except that Codex subscription gets pretty hefty token space.
For example, I pass it a list of database collections and tools to search through them, ask a question that can very obviously be answered with them, and it responds with "I can’t tell yet from your current records" (just tested with GPT 5.4-mini).
But I've prodded it a bit more now, and maybe the model doesn't want to answer unless it can be very very confident of the answer it produces. So it's sort of a "soft refusal".
For anything else, I can't stand them, and it genuinely feels like I am interacting with different models outside of codex:
- They act like terribly arrogant agents. It's just in the way they talk: self-assured, assertive. They don't say they think something, they say it is so. They don't really propose something, they say they're going to do it because it's right.
- If you counter them, their thinking traces are filled with what is virtually identical to: "I must control myself and speak plainly, this human is out of his fucking mind"
- They are slow. Measurably slow. Sonnet is so much faster. With Sonnet models, I can read every token as it comes, but it takes some focusing. With GPT, I can read the whole trace in real-time without any effort. It genuinely gives off this "dumb machine that can't follow me" vibe.
- Paradoxically, even though they are so full of themselves, they insist upon checking things which are obvious. They will say "The fix is to move this bit of code over there [it isn't]" and then immediately start looking at sort of random files to check...what exactly?
- I feel they make perhaps as many mistakes as Sonnet, but they are much less predictable mistakes. The kind that leaves me baffled. This doesn't have to be bad for code quality: Sonnet makes mistakes which _might_ at points even be _harder_ to catch, so might be easier to let slip by. Yet, it just imprints this feeling of distrust in the model which is counter-productive to make me want to come back to it
I didn't compare either with Gemini because Gemini is a joke that "does", and never says what it is "doing", except when it does so by leaving thinking traces in the middle of python code comments. Love my codebase to have "But wait, ..." in the middle of it. A useless model.
I've recently started saying this:
- Anthropic models feel like someone of that level of intelligence thinking through problems and solving them. Sonnet is not Opus -- it is sonnet-level intelligence, and shows it. It approaches problems from a sensible, reasonably predictable way.
- Gemini models feel like a cover for a bunch of inferior developers all cluelessly throwing shit at the wall and seeing what sticks -- yet, ultimately, they only show the final decision. Almost like you're paying a fraudulent agency that doesn't reveal its methods. The thinking is nonsensical and all over the place, and it does eventually achieve some of its goals, but you can't understand what little it shows other than "Running command X" and "Doing Y".
On a final note: when building agentic applications, I used to prefer GPT (a year ago), but I can't stand it now. Robotic, mechanic, constantly mis-using tools. I reach for Sonnet/Opus if I want competence and adherence to prompt, coupled with an impeccable use of tools. I reach for Gemini (mostly flash models) if I want an acceptable experience at a fraction of the price and latency.
Oh I feel that. I sometimes ask ChatGPT for "a review, pull no punches" of something I'm writing, and my god, the answers really get on my nerves! (They do make some useful points sometimes, though.)
> On a final note: when building agentic applications, I used to prefer GPT (a year ago), but I can't stand it now. Robotic, mechanic, constantly mis-using tools. I reach for Sonnet/Opus if I want competence and adherence to prompt, coupled with an impeccable use of tools. I reach for Gemini (mostly flash models) if I want an acceptable experience at a fraction of the price and latency.
Yeah, this has been almost exactly my experience as well.
Would you mind expanding on this? Do you mean in the resulting code? Or a security problem on your local machine?
I naively use models via our Copilot subscription for small coding tasks, but haven't gone too deep. So this kind of threat model is new to me.
I don't use OpenCode but looks like it also triggered similar use. My message was similar but different.
GPT 5 mini: Input $0.25 / Output $2.00
GPT 5 nano: Input: $0.05 / Output $0.40
GPT 5.4 mini: Input $0.75 / Output $4.50
GPT 5.4 nano: Input $0.20 / Output $1.25
Why expect cheaper then? The performance is also better
Care to share the parameter counts for them?
Most "Model X > Model Y" takes on HN these days (and everywhere) seem based on an hour of unscientific manual prompting. Are we actually running rigorous, version-controlled evals, or just making architectural decisions based on whether a model nailed a regex on the first try this morning?
It's evident in the fact that every time AI has historically met certain thresholds (chess-playing, the Turing Test, fluent language), we play with them a little more and find out there's something still lacking.
If questions are fixed they are trivial to game.
Evals are broken - OpenAI showed that SWE Bench Verified was in the training data - models were able to reconstruct the changes from memory (https://openai.com/index/why-we-no-longer-evaluate-swe-bench...)
However, this doesn't mean we should completely give up on benchmarking. In fact, as models get more intelligent, and we give them more autonomy, I believe that tracking agent alignment to your coding standards becomes even more important.
What I've been exploring is making a benchmark that is unique per-repo - answering the question of how does the coding agent perform in my repo doing my tasks with my context. No longer do we have to trust general benchmarks.
Of course there will still be difficulties and limitations, but it's a step towards giving devs more information about agent performance, and allowing them to use that information to tweak and optimize the agent further
Evals are bad because people learn and fit to them. So we do extremely small evals instead.
So there is a definite advantage to never publicizing your internal benchmark. But then, no one else can replicate your findings. You should assume that the space of benchmarks that are actually decent at evaluating model performance is much larger and most of the good ones, the ones that were costliest to produce, are hidden, and might not even correspond very well with the public ones. And that the public expensive benchmarks are selective and have a bias towards marketing purposes.
Also context bleed into nano subagents in multi-model pipelines — I've seen orchestrators that just forward the entire message history by default (or something like messages[-N:] without any real budgeting), so your "cheap" extraction step suddenly runs with 30-50K tokens of irrelevant context. And then what's even the point, you've eaten the latency/cost win and added truncation risk on top.
Has anyone actually measured where that cutoff is in practice? At what context size nano stops being meaningfully cheaper/faster in real pipelines, not benchmarks.
For many "simple" LLM tasks, GPT-5-mini was sufficient 99% of the time. Hopefully these models will do even more and closer to 100% accuracy.
The prices are up 2-4x compared to GPT-5-mini and nano. Were those models just loss leaders, or are these substantially larger/better?
GPT-5.4-nano is less impressive. I would stick to gpt-5.4-mini where precise data is a requirement. But it is fast, and probably cheaper and better quality than an 8-20B parameter local model would be.
( https://encyclopedia.foundation/benchmarks/dashboard/ for details - the data is moderately blurry - some outlier (15s) calls are included, a few benchmark questions are ambiguous, and some prices shown are very rough estimates ).
We have a legacy Win32 application, and we want to side-by-side compare interactions + responses between it and the web-converted version of the same. Once you've taught the model that "X = Y" between the desktop Vs. web, you've got yourself an automated test suite.
It is possible to do this another way? Sure, but it isn't cost-effective as you scale the workload out to 30+ Win32 applications.
Did GPT write them?
5.4 mini seems to struggle with consistency, and even with temperature 0 sometimes gives the correct response, sometimes a wrong one...
[0]: https://aibenchy.com/compare/openai-gpt-5-4-medium/openai-gp...
GPT 5.4 mini is the first alternative that is both affordable and decent. Pretty impressed. On a $20 codex plan I think I'm pretty set and the value is there for me.
So, in opencode you'd make a "PR Meister" and "King of Git Commits" agent that was forced to use 5.4mini or whatever, and whenever it fell down to using that agent it'd do so through the preferred model.
For example, I use the spark models to orchestrate abunch of sub-agents that may or may not use larger models, thus I get sub-agents and concurrency spun up very fast in places where domain depth matter less.
[0]: https://developers.openai.com/codex/config-advanced#profiles [1]: https://opencode.ai/docs/agents/
Is there any harness with an easy way to pick a model for a subagent based on the required context size the subagent may need?
Preregistering my predictions:
Mini: better than Haiku but not as good as Flash 3, especially at reasoning=none.
Nano: worse than Flash 3 Lite. Probably better than Qwen 3.5 27b.
OpenAI restructures after Anthropic captures 70% of new enterprise deals. Claude Code hits $2.5B while Codex lags at $1B ahead of dual IPOs.
Src: https://www.implicator.ai/openai-cuts-its-side-quests-the-en...
I think, no model, SOTA or not, has neither the context nor the attention to be able to do anything meaningful with huge amount of logs.
Direct image: https://pbs.twimg.com/media/HDoN4PhasAAinj_?format=png&name=...
I assume that OpenAI continue to use words like "mini" and "nano" in the names of these model variants, to imply that they reserve the smallest possible resource-units of their inference clusters... but, given OpenAI's scale, that may well be "one B200" at this point, rather than anything consumers (or even most companies) could afford.
I ask because I'm curious whether the economics of these models' use-cases and call frequency work out (both from the customer perspective, and from OpenAI's perspective) in favor of OpenAI actually hosting inference on these models themselves, vs. it being better if customers (esp. enterprise customers) could instead license these models to run on-prem as black-box software appliances.
But of course, that question is only interesting / only has a non-trivial answer, if these models are small enough that it's actually possible to run them on hardware that costs less to acquire than a year's querying quota for the hosted version.
IIRC, GPT-3 itself was admitted to be a 175B model, and its reduced variants were disclosed to have parameter-counts like 1.3B, 6.7B, 13B, etc.
Seriously?
If I told it I'm shopping for a budget-level Mac, it may not recommend the Neo. I'm sure software only moves faster, too. Especially as more code is 'written' blindly, new stacks may never see adoption
So there's no major update in the sense that you might be thinking. Most of the time there's not even an announcement when/if training cut offs are updated. It's just another byline.
A 6 month lag seems to be the standard across the frontier models.