Andrej Karpathy (@karpathy)

The reality of building web apps in 2025 is that it's a bit like assembling IKEA furniture. There's no "full-stack" product with batteries included, you have to piece together and configure many individual services: - frontend / backend (e.g. React, Next.js, APIs) - hosting (cdn, https, domains, au...

I wrote a quick new post on "Digital Hygiene". Basically there are some no-brainer decisions you can make in your life to dramatically improve the privacy and security of your computing and this post goes over some of them. Blog post link in the reply, but copy pasting below too. Every now and the...

When working with LLMs I am used to starting "New Conversation" for each request. But there is also the polar opposite approach of keeping one giant conversation going forever. The standard approach can still choose to use a Memory tool to write things down in between conversations (e.g. ChatGPT do...

GPT 4.5 + interactive comparison :) Today marks the release of GPT4.5 by OpenAI. I've been looking forward to this for ~2 years, ever since GPT4 was released, because this release offers a qualitative measurement of the slope of improvement you get out of scaling pretraining compute (i.e. simply tr...

I quite like the idea using games to evaluate LLMs against each other, instead of fixed evals. Playing against another intelligent entity self-balances and adapts difficulty, so each eval (/environment) is leveraged a lot more. There's some early attempts around. Exciting area. <a target="_blank" hr...

There's a new kind of coding I call "vibe coding", where you fully give in to the vibes, embrace exponentials, and forget that the code even exists. It's possible because the LLMs (e.g. Cursor Composer w Sonnet) are getting too good. Also I just talk to Composer with SuperWhisper so I barely even to...

One of my favorite applications of LLMs is reading books together. I want to ask questions or hear generated discussion (NotebookLM style) while it is automatically conditioned on the surrounding content. If Amazon or so built a Kindle AI reader that “just works” imo it would be a huge hit. For now...

# automating software engineering In my mind, automating software engineering will look similar to automating driving. E.g. in self-driving the progression of increasing autonomy and higher abstraction looks something like: 1. first the human performs all driving actions manually 2. then the AI he...

New (2h13m 😅) lecture: "Let's build the GPT Tokenizer" Tokenizers are a completely separate stage of the LLM pipeline: they have their own training set, training algorithm (Byte Pair Encoding), and after training implement two functions: encode() from strings to tokens, and decode() back from token...