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by materielle 15 days ago
I'm about to leave a shallow comment, but I am a bit skeptical of the supposed drop in inference costs. If AI labs saw a lot of potential there, they'd surely be bragging about it non-stop? So the fact that publicly available information is conflicted is probably a sign that at the very least, the numbers aren't amazing.

Yes I know there's no evidence and this is lazy reasoning. But there's probably a bit of truth to this line of thought.

6 comments

Why on earth would AI labs be bragging about how little the product they sell actually costs them to make? You don't want to do anything that reduces it's perceived value to the user, that might make them less willing to pay for it.

Also, inference costs are bound to go way down with more optimized architectures. GPUs are fundamentally not great at inference. No platform where the weights are streamed from a large pool of memory is. If the models ever quiet down, there will be massive step changes in cost/token, energy/token and tokens/second, as models are etched into silicon ala https://chatjimmy.ai/

A couple of years ago Altman was saying the price of AI compute is going to drop 90% year over year or something like that, so I don't think they're nervous about talking about lowering their costs. They probably just haven't been able to lower their costs.

You have to keep in mind that about 99% of their announcements are targeted towards investors (their most important revenue source..), so they're not going to be afraid to mention metrics that make the business look better.

Jevons paradox. Cheaper tokens does not mean we will spend less.
Cheaper tokens means the company's margins increase, which would be valuable for investors to hear
The main limit to my token spend right now is that I'm running out of hours in a day.
Ah yes, Sam “Not Consistently Candid” Altman
Oh, is that the guy that sold Loopt by claiming it had hundreds of thousands of users and it turned out to have 500 DAU after his exit?
Yep, the very same scammer. Wonder if he's lying about OpenAI too? Maybe about a person blowing a metal instrument?
he lied. he's good at that.
Why would any company brag about their margins ? Yet they do, to attract investors.
The key AI labs are not public companies, they are at liberty to brag about their margins to potential investors in private.
And investors will leak such claims quickly enough that this reasoning cannot plausibly hide big secrets.
It's not a big secret. If you just do the math yourself, it's easy to compute that inference doesn't cost all that much. People just see all the capital investment going around and all the new data centers being built, see that it's spent on "AI", put two and two together and get a three, or "clearly serving AI requests costs an arm and a leg".

The 1 they were missing is that AI requires both training and inference, and training is by far the expensive part. And that in principle you can stop training at any point and keep using the models as they are. (But that means that if other companies keep improving their models, you'll be left behind...)

In contrast, inference is fairly cheap and all the providers have great margins on it. Eventually either investment in training stops having commensurate impact on model quality, and people stop doing that and instead concentrate on making inference faster and even more efficient. Or if that doesn't happen, things will get very weird very quickly.

The market already shows where it will go.

If you want frontier model you will pay more for inference to essentially fund the expensive training.

If you don’t need frontier model you will get dirt cheap inference, which eventually will approach the cost of electricity spent per token.

This is technically correct, but practically false.

They can't stop training as then the AI's knowledge will become out-of-date very quickly. Their knowledge stops the day you stop training.

> If you just do the math yourself, it's easy to compute that inference doesn't cost all that much.

Show us your work, then. If it's so easy to do, this should be a trivial request to accommodate, no?

I’m wary of “has not been leaked in a way that was picked up in public news” as proof or disproof of anything.
this is changing soon
Not really, how much of a public company are you when 5% of your capital is public ?
That doesn't matter for the legal requirements.

The short and only kind of wrong version is:

In the US, companies are not allowed to unfairly privilege some investors over others by giving them access to secret information that would let them judge the future prospects of the company. (Except in all the ways they can, but these usually involve some kinds of insider trading rules.) Private companies can handle giving out secrets to investors by literally writing and memo and mailing it to all their investors, if they want to give out some secrets to one of them.

Public companies cannot do that, even if they knew who all their investors were, but must instead consider every member of the public a potential investor, even if they don't already own the stock. Because of this, when public companies want to reveal material information about their future prospects, they must reveal it to everyone.

The percentage is irrelevant for this discussion. As soon as you’re public, you need to report detailed financial numbers.
Isn't there a limit on the public markets where if a company has less than a certain percentage of its ownership traded publicly then it is no longer a public company and therefore de-listed?

I remember hearing about a guy trying to squeeze out short sellers of his own company but ended up effectively taking his company private because he bought out like 95% of all the shares.

I wonder how that aligns to these small releases of stock for the public.

Growing companies don't brag about their margins, they brag about their growth and revenue. Margin talk is for when you're a mature company squeezing out every bit of profitability you can - if anything it would be a negative sign to be worrying about your margins when you're supposed to still be growing and innovating.
I mean, did anyone expect them to not have margins? Why keep it secret?
> Why on earth would AI labs be bragging about how little the product they sell actually costs them to make? You don't want to do anything that reduces it's perceived value to the user, that might make them less willing to pay for it.

Wouldn't they be bragging about it to investors? It feels like something that would matter a lot to them, and at least OpenAI kinda feels desperate to find them.

There's also the small question about whether a drop in inference cost would actually change anything about profitability, when training seems to get exponentially more expensive.

Because companies that want to go public need to look profitable or potentially profitable. And before they go public they have to release real, actual, legally demonstrable numbers for their costs and revenue anyway.
When they will actually file to go public, their numbers will be intensely scrutinized. That's all that global headlines will be talking about for weeks on end. Why would they create forward expectations before it's necessary?

Of course they don't want to create forward expectations in a volatile macro environment, with the public listing being 6 months out.

Because the most important thing for any pure play AI company right now is to prove they are a viable company. And sure they have proved they can make billions, but also that they can lose billions more. They are going to need even more money and to prove to the next round of investors at an even higher valuation that they are a viable business they need to show not that they can generate revenue, but that they can one day turn a healthy profit. And that is the trillion dollar question.
I doubt having to replace every single chip in your data center every time you release a new model will bring down costs.
Went to that URL asked one question - "how is this different from other AI" and it took 598/6144 tokens, not sure what that means.
Not super clear from the site itself, but this LLM is running on specialized silicon implementing just it. So has super low energy use and blazing speed.

See https://taalas.com/products/

Edit: updated link

Incredible increase over Nvidia! Need to read more.. Thanks!
Because they can think more than one quarter into the future? Why on earth would someone adopt something into their core workflow that was fantastically unprofitable? Uncertainty and business don’t mix. Most people aren’t hype-eating bacteria that only care about maximizing their next paycheck.
One reason is that all the code you write with this goes in your private git. If using AI no longer is possible because of cost, you can still profit a lot from what you did with it before.
For consultants? Sure. What percentage of contractors are consultants? And is that better than going with something in your stack that’s sustainable even if it’s not totally optimal? I’d wager most would say no.
Regardless of profitability there will always be multiple good LLM vendors as well as open-source alternatives (slightly worse but still pretty good). If one vendor fails then it's easy to switch your core workflow to a competitor.
On an individual basis for coding? Sure. If you’re a significant business with agents that do more nuanced work, which is the only kind of customer that will let any of these companies pay back those trillions of dollars as quickly as they need to to stay alive, these are not fungible services.
I wonder if inference costs will go down...

or will it be like microsoft office, where the software bloats to use/fill current hardware?

(and in this case bloats might mean better thinking or pulling in more data)

If inference costs drop 90% or whatever, that would be a massive write-off of hardware even before they gave any returns for it?! Given Chinese and others are snapping at the heels and would also benefit from such reduction in cost.
> Why on earth would AI labs be bragging about how little the product they sell actually costs them to make?

Investor confidence. They have a bit of a need for cash (also an interesting part of the profitability discussion of course).

> Also, inference costs are bound to go way down with more optimized architectures

I agree. Jimmy is incredible, I wonder what non-toy use cases they have. Surely they’ll come out with updated chips soon.

That said, I was apparently a bit over-excited for Groq and Cerebras. I thought they’d quickly dethrone Nvidia for inference, but not so far. Even the GPT spark trial isn’t seeming to go far.

Inference has traditionally been far less expensive than training. One public example is the fact that hobbyists can run StableDiffusion ($600k training costs[1]) on their personal computers.

Speaking to your point, inference being dramatically less costly than training would not be seen as a delta from the norm. The model of providing inference for anything near the operational costs (like a utility would), would the delta from the norm if it were true.

[1] https://x.com/emostaque/status/1563870674111832066

The difference between training and inference is 1) one have to keep intermediate results for backward pass in training and 2) computation for training double because of the backward pass.

Training is also done over batches, which increase memory requirements by several orders of magnitude. This is why training needs costly compute.

One of the ways out of this unfortunate situation is to use something like Stochastic Average Gradient Descent [1]. Examples there are mostly concerned with regularized logistic regression, which makes problem more or less convex. Neural networks are inherently non-convex. Still, maybe some ideas from there can be utilized in the context of neural networks, like use of estimated Lipshitz constant to derive curvature and appropriate learning step.

  [1] https://www.cs.ubc.ca/~schmidtm/Courses/540-W19/L12.pdf
So one way to think about it is roughly,

Training is inference + backwards pass (~2x inference cost) + activations (vram overhead) + optimizer (vram overhead) + gradients (vram overhead).

Multiply "inference + backwards pass (~2x inference cost) + activations (vram overhead)" by batch size (thousands) to get to the actual RAM and compute cost. Optimizer like ADAM adds only two or three model-sized overhead.

And last, but not least, you need only one hidden layer kept in RAM for inference, but you need all of them (61 for Deepseek models) kept in RAM for computing gradient for one sample.

Microbatch size is a hyperparameter, it can be set to 1 and work just as effectively. With gradient accumulation it's equivalent even. Large batch sizes are used to increase parallelism, and sometimes to reduce variance in the loss signal (at the cost of increased bias).

Batch size is frequently limited by compute bottlenecks well before memory.

And of course you do all of this for every object in your training set, which is going to be larger than the total number of uses for any individual user.
Does it matter what is the difference in size of needed inputs for inference vs. training?
That is an estimate of the relative cost of one training step, but you have to multiply it by the number of training steps, an unknown quantity.
It's all got much more complex than that in recent years. Training now involves large amounts of inference for RL rollouts and similar. You can't disentangle them computationally like that. "Inference" is just the word used to mean serving customer traffic now, and "training" means creating the model you serve.
I think in your StableDiffusion example, a lot more than $600k will have been spend on electricity alone for inference (on those personal computers you mention). So inference is more expensive then training.
For equal capability tokens, there has been about a 10x drop in cost every 6 months.

We are still chasing the best because the best is moving rapidly, but it’s a simple thought experiment to work out what the cost to serve an 8B model from 2 years ago is in a world of 2T models.

Note: parameter counts are illustrative. Concretely, qwen3.6 27B delivers opus 4.5 capability at 1/27th the cost on openrouter. Single chip llama3 8b performance can exceed 17k tokens/sec.

8B models would be consider obsolete in the world of 2T models, at least if we're talking about the competitiveness of OpenAI/Anthropic. The only reason why they are valued so highly is their supposed dominance at the top end.
The main story of agent use cases is in enterprise so far. An enterprise will only pay for a model capable of handling the task and no more. Most enterprise's see no need to hire PhDs as factory line workers.

Coding is an interesting case as [1] the pace of progress has been absurd and [2] it's hard to put an upper bound on required capability. However hard to put a bound on and will are different, it's quite possible that the average engineer will cease to see the benefit of rapid progress - or that their employer will be satisfied with lower tier models.

How smart of a model do you need to build a high quality CRUD app for internal users? Or build a scalable web service?

yes, which is why the revenue growth story is not looking so great for Anthropic/OpenAI, when open-source alternatives are not far behind with much lower costs.
> For equal capability tokens, there has been about a 10x drop in cost every 6 months

Is this still happening? Opus 4.5 was six months ago, can you get its capabilities for 1/10 cost now? Are we on track to get the same for 4.6 in a couple months?

Pretty much, Kimi K2.6 is opus 4.6 quality for coding. If you include discounts due to more efficient input caching it is around 1/10th of opus4.6.

https://openrouter.ai/moonshotai/kimi-k2.6

The march of cost efficiency moves on.

Why haven’t I heard of this? Is it available in IDEs like Cursor?
> I am a bit skeptical of the supposed drop in inference costs. If AI labs saw a lot of potential there, they'd surely be bragging about it non-stop?

Unless to the grandparent commenter’s point they’re using it to obscure their large prisoner’s dilemma (training) cost?

> If AI labs saw a lot of potential there, they'd surely be bragging about it non-stop?

Google seems to pretty regularly post about how their TPU and algorithm advancements have been decreasing energy costs for both inference and training.

What other companies brag about lowered costs? Isn’t that just a complicated way of asking customers to demand lower prices?