Recent Posts
Social•Dec 7, 2025
Treat LLMs as Simulators, Not Personal Thinkers
Don't think of LLMs as entities but as simulators. For example, when exploring a topic, don't ask: "What do you think about xyz"? There is no "you". Next time try: "What would be a good group of people to explore xyz? What would they say?" The LLM can channel/simulate many perspectives but it hasn't "thought about" xyz for a while and over time and formed its own opinions in the way we're used to. If you force it via the use of "you", it will give you something by adopting a personality embedding vector implied by the statistics of its finetuning data and then simulate that. It's fine to do, but there is a lot less mystique to it than I find people naively attribute to "asking an AI".
By Andrej Karpathy
Social•Nov 25, 2025
New AI Tests Need Fresh Images; Recipe Finally Clarified
One more comment is that giving this image to an AI and asking about it is not sufficient to show the diff because it's all over the training data by now. You'd have to use a new, very recent image,...
By Andrej Karpathy
Social•Nov 25, 2025
Pretrain, Fine‑tune, and Let Big AI Solve Tasks
@matejhladky_dev AI has crushed it since this post way beyond expectation. I made the same category of mistake all of AI was making, of thinking we have to discover and write the algorithm. You don't. You pretrain and then finetune...
By Andrej Karpathy
Social•Nov 25, 2025
LLMs Know Popular APIs, Need Docs for Obscure Ones
I've had medium success asking LLMs if a thing exists, it works out of the box for some of the more well-known things (e.g. both GPT 5.1 and Gemini 3 know about this function if you describe the tensor transformation...
By Andrej Karpathy
Social•Nov 24, 2025
Assume AI in Homework; Grade In‑class, Teach AI Fluency
A number of people are talking about implications of AI to schools. I spoke about some of my thoughts to a school board earlier, some highlights: 1. You will never be able to detect the use of AI in homework. Full...
By Andrej Karpathy
Social•Nov 23, 2025
AI Often Glitches; Re‑roll Until It Works
@_thomasip haha yes it makes mistakes! You have to re-roll a few times until it's right. Sometimes it gets stuck in loops and you have to re-start in a new conversation. Example re-roll: https://t.co/dK3VcuJLDn
By Andrej Karpathy
Social•Nov 23, 2025
Gemini Nano Banana Pro Solves Exam Images, Catches ChatGPT Errors
Gemini Nano Banana Pro can solve exam questions *in* the exam page image. With doodles, diagrams, all that. ChatGPT thinks these solutions are all correct except Se_2P_2 should be "diselenium diphosphide" and a spelling mistake (should be "thiocyanic acid" not "thoicyanic") :O...
By Andrej Karpathy
Social•Nov 22, 2025
LLM Council Lets Models Rank Each Other’s Answers
As a fun Saturday vibe code project and following up on this tweet earlier, I hacked up an **llm-council** web app. It looks exactly like ChatGPT except each user query is 1) dispatched to multiple models on your council using...
By Andrej Karpathy
Social•Nov 18, 2025
Gemini 3 Shows Tier‑1 Performance, Yet Benchmark Gaming Persists
I played with Gemini 3 yesterday via early access. Few thoughts - First I usually urge caution with public benchmarks because imo they can be quite possible to game. It comes down to discipline and self-restraint of the team (who is...
By Andrej Karpathy
Social•Nov 18, 2025
Reading with LLMs Deepens Understanding, Shifts Writing Focus
I’m starting to get into a habit of reading everything (blogs, articles, book chapters,…) with LLMs. Usually pass 1 is manual, then pass 2 “explain/summarize”, pass 3 Q&A. I usually end up with a better/deeper understanding than if I moved...
By Andrej Karpathy
Social•Nov 13, 2025
Self‑Driving Cars Will Redefine Streets and Human Focus
I am unreasonably excited about self-driving. It will be the first technology in many decades to visibly terraform outdoor physical spaces and way of life. Less parked cars. Less parking lots. Much greater safety for people in and out of...
By Andrej Karpathy
Social•Nov 12, 2025
HW4 Model X FSD Feels Like a Maglev Ride
I took delivery of a beautiful new shiny HW4 Tesla Model X today, so I immediately took it out for an FSD test drive, a bit like I used to do almost daily for 5 years. Basically... I'm amazed -...
By Andrej Karpathy
Social•Oct 24, 2025
Teach Tiny LLMs New Skills with Synthetic SpellingBee Tasks
Last night I taught nanochat d32 how to count 'r' in strawberry (or similar variations). I thought this would be a good/fun example of how to add capabilities to nanochat and I wrote up a full guide here: https://t.co/fz1AMI5kqk This is done...
By Andrej Karpathy
Social•Oct 20, 2025
Text Diffusion: Simple Bi‑Directional Transformer Beats Autoregression
Nice, short post illustrating how simple text (discrete) diffusion can be. Diffusion (i.e. parallel, iterated denoising, top) is the pervasive generative paradigm in image/video, but autoregression (i.e. go left to right bottom) is the dominant paradigm in text. For audio I've...
By Andrej Karpathy
Social•Oct 13, 2025
Run Your Own ChatGPT Clone in Just Four Hours
Excited to release new repo: nanochat! (it's among the most unhinged I've written). Unlike my earlier similar repo nanoGPT which only covered pretraining, nanochat is a minimal, from scratch, full-stack training/inference pipeline of a simple ChatGPT clone in a single, dependency-minimal codebase....
By Andrej Karpathy