we've been testing some new methods for improving writing quality. you may have seen Sam Altman's demo in late march; GPT-5-thinking uses similar ideas it doesn't make a lot of sense to talk about better writing or worse writing and not really worth the debate. i think the model

GPT-5 rollout updates: *We are going to double GPT-5 rate limits for ChatGPT Plus users as we finish rollout. *We will let Plus users choose to continue to use 4o. We will watch usage as we think about how long to offer legacy models for. *GPT-5 will seem smarter starting

PSA: Add ". think hard" to the end of all your ChatGPT GPT5 prompts. In my testing, so far that has resulted in it using the competent model 100% of the time. And so far, not adding it has resulted in it using the crippled model 100% of the time, which has failed all my tasks.

From 49th to 98th percentile in IOI in a single year. Insane progress.

I think congrats again to OpenAI for cooking with GPT-5 Pro. This is the third time I've struggled on something complex/gnarly for an hour on and off with CC, then 5 Pro goes off for 10 minutes and comes back with code that works out of the box. I had CC read the 5 Pro version

Been managing multiple GPT-5-high in the Codex CLI for a while, and they just keep delivering. Excited to try the new model!

We have updated ChatGPT's personalization page: personality configuration, custom instructions, and memories are now all in one place. Going live over the next couple of days.

Goals with ChatGPT.

Sound on.

Sora 2 is here.

We made ChatGPT pretty restrictive to make sure we were being careful with mental health issues. We realize this made it less useful/enjoyable to many users who had no mental health problems, but given the seriousness of the issue we wanted to get this right. Now that we have

You should never use an em dash in your writing anymore. You will 100% be accused of using AI, especially if its on social.

We are making it easier to customize ChatGPT's tone and style! New options such as Professional, Candid, Quirky are available, and we updated Friendly (formerly Listener), and Efficient (formerly Robot)! We are iterating fast on those tone and style options, with feedback from

Xiangning Chen significantly boosted the custom instruction following capabilities for 5.1!! Here is a quick comparison with the custom instructions "do not use em-dash!" for GPT-5 and GPT5.1. Amazing work! openai.com/index/gpt-5-1/

GPT-5.1 does NOT use em dashes anymore—in case it is specified in custom instructions! Instruction following is also getting much better in comparison to GPT-5.

GPT-5.1 is an underrated upgrade Custom instructions are key to getting the most out of LLMs Longer post on this coming soon

for the first time 5.1 instant uses adaptive reasoning when responding. shipping this led the team down some pretty fun ML rabbit holes! if you’re an RL nerd, please reach out 🙂 I’ll be at neurips looking for folks to join the Science of Posttraining team

Small-but-happy win: If you tell ChatGPT not to use em-dashes in your custom instructions, it finally does what it's supposed to do!

Group chats in ChatGPT are now rolling out globally. After a successful pilot with early testers, group chats will now be available to all logged-in users on ChatGPT Free, Go, Plus and Pro plans.