OpenAI launched ChatGPT Work on July 9th and hasn’t stopped tweaking it since. Simon Willison spent weeks poking at the product and reports that it’s “an extraordinarily confusing and very powerful product.” His breakdown, published August 30th, is the clearest map anyone has drawn of what this thing does. Here’s a practical guide to using it, built entirely on what Willison figured out.
Quick Start: what you’ll learn and what you need
By the end of this guide you’ll know when to reach for ChatGPT Work instead of regular Chat, and which of its standout features actually matter. What you need: a paid ChatGPT subscription at $20/month or higher. Free users and $8/month Go users are locked out. This guide focuses on the cloud version of Work, accessed through chatgpt.com or the mobile apps.
Step 1: Know there are two products
Before anything else, understand that “ChatGPT Work” refers to two different things. The cloud version runs on OpenAI’s servers and is reached via chatgpt.com or the mobile apps. Willison calls this one Work Cloud. The other version lives inside the ChatGPT desktop app (formerly called Codex) and can touch files and run programs on your own machine. He calls that Work Local, and describes it as “regular Codex re-skinned to be less intimidating to non-software-developers.” Everything below is about Work Cloud.
Step 2: Find Work in the interface
Work shows up as a tab selector, presented as an alternative to Chat. OpenAI’s official guidance says to use Chat for answers, explanations, brainstorms, or short drafts, and use Work when you want a finished task with a clear outcome. Willison finds that advice nearly useless, since he’s done all of those in regular Chat for years. The sharper question is what Work can do that Chat can’t. That’s where the real value sits.
Step 3: Pick your model
Work lets you choose GPT-5.6 Sol, Luna, or Terra, each with reasoning levels from Light up to Ultra. You can also select GPT-5.5. These appear to be the same models offered through the OpenAI API. Chat gives you a different, narrower menu, and $20/month subscribers there cap out at High. Willison believes Work sessions bill against your Codex allowance while Chat gets its own separate pool, which likely explains the difference. One tip from his Codex use: Ultra mode more eagerly hands work off to sub-agents.
Step 4: Run code with real internet access
This is the feature Willison is most excited about. Work’s code execution environment can reach the open internet, something Chat blocks through its container proxy. Claude’s equivalent has allowed limited access since last September, but only a short allowlist of domains. Work’s default appears open to everything. That means you can clone GitHub repositories, install their dependencies, and use them to interact with the wider web. You can also lock it down to a specific list of allowed domains when you need to.
Step 5: Drive a full headless browser
Work can launch a full Chrome instance, load sites, fill forms, take screenshots, and run JavaScript against the page. If a site needs a login, the browser can hand control back to you for passwords and 2FA codes without routing those credentials through the model. Willison tested it with this prompt: “Load simonwillison.net in your browser and extract the headings using JavaScript.” Work spun up a browser and ran Playwright code to pull every heading. His reaction: it works like his own shot-scraper tool, except now he can run it from his phone.
Step 6: Use the persistent filesystem
Chat wipes its filesystem after every session. Work gives each session a scratch folder that persists across sessions, so you can reach files from earlier chats. Willison has 171 folders sitting in his workspace right now. The volume is shared across running Work sessions, so a file edited in one appears instantly in another. Processes aren’t shared, though, so a localhost server in one session isn’t reachable from another.
Step 7: Build and deploy real sites
Work can build and ship entire websites on Cloudflare Workers, with HTML, JavaScript, and server-side features including Cloudflare D1 and R2 storage. Willison built a live demo site this way from a single prompt.
Where to go next
Start small: pick one repetitive task, try it in Work with internet access on, and compare the result against Chat. Then test the browser tool on a site you visit daily. Willison’s full write-up has more detail and examples worth reading at the source.