Founded in August 2019, The Browser Company set out with an ambitious vision: to reshape the way we experience the internet.
The company introduced Arc, a Chromium-based browser crafted in Swift, with a bold aim to function more like an operating system for the web. Featuring advanced tools for website customization and a sleek, productivity-oriented interface, Arc was a fresh take on how browsers should serve users—not just show them webpages.
Riding on the momentum, the team launched Arc Search, a mobile-first browsing experience that broke away from conventional search engines. By pulling insights from across the web and presenting summarized, curated results, Arc Search aimed to simplify information discovery and make browsing feel intuitive.
Their mission was bold yet simple: reimagine web browsing from the ground up.
However, the digital landscape shifted dramatically with the explosion of large language models (LLMs), sparked by OpenAI’s introduction of ChatGPT. This breakthrough redefined how people engage with information, making traditional search feel outdated.
In response, The Browser Company pivoted. They paused development on Arc and redirected their focus toward building 'Dia'—a new AI-powered browser designed for the post-LLM era.
After hinting the launch of Dia a day prior, The Browser Company finally reveals Dia in beta.
Meet Dia. Now available for Arc members. pic.twitter.com/KP0GvgeByp
— Dia (@diabrowser) June 11, 2025
The idea, is to make a browser that can be highly personalized by its users.
But unlike other browsers that can have their appearance and functionalities customizable, Dia uses AI to customize the experience of browsing, which is in line with what The Browser Company has in mind since the very beginning.
As the successor of Arc, Dia uses AI to learn from users interactions with the web, in order to understand their interest and needs.
"With every tab that you open, it should feel like this AI model is getting more and more personalized to you, such that at the end of a week of browsing, a month of browsing, let alone a year, it’s going to know you as well as your closest friends and colleagues," said Josh Miller, CEO of The Browser Company.
First, how it works:
Every time you open a new tab, Dia's memory automatically takes notes for you.
It's like Granola for browser tabs.
(These notes are encrypted & stored locally. We don’t take notes on sensitive pages like banking.)
Here’s how to turn it on in Dia: pic.twitter.com/tR97L4GiAr— Josh Miller (@joshm) June 11, 2025
Based on this ability, and also AI, users can ask Dia about pretty much everything, and have the browser return answers based on their tabs.
These tabs act like the 'memory' feature on other LLMs like ChatGPT, but unlike on rivals, Dia's memory can span to thousands of tabs in which if can refer to..
In Dia's own words, the browser brings "tabs to life" so users have to "never explain yourself again."
…or think of Dia as a co-worker who’s been browsing by your side all along — and knows what you know.
It can draft documents in your voice, without you copying, pasting, or uploading a thing.
Notice I don’t explain anything here — Dia just knows: pic.twitter.com/zInJ6THWrr— Josh Miller (@joshm) June 11, 2025
Dia can act like a coach, therapist, or advisor as well — combining the IQ of frontier LLMs with the EQ of the rich personal context (and taste) reflected in your tabs.
It might feel a little weird at first, but you can now ask things like this: pic.twitter.com/FjGjJ1peGP— Josh Miller (@joshm) June 11, 2025
To experience this, Dia’s URL bar acts as the main interface for its in-built AI chatbot.
With it, users can not ask Dia to answer about all the tabs they have opened, as they can have the bot write up a draft based on the contents of those tabs. Then, they can also have the browser browse the web for them, summarize files they upload.
Dia can also automatically switch between chat and search functions.
Your memories in Dia – drawn from 1000s of tabs each month – are clearly a new kind of software play-doh.
But we're nowhere close to discovering what it’s truly best at yet. We need your help!
Tho the moment @hursh sent this from a prototype, I knew we were onto something… pic.twitter.com/0ksnAcUhTP— Josh Miller (@joshm) June 11, 2025
Miller acknowledged the growing trend of people turning to AI tools for a wide variety of tasks. In response to this, Dia is a direct reflection of this shift.
By embedding an AI-powered interface directly within the browser, where so much of users’ daily work already happens, Dia aims to seamlessly integrate into existing workflows. The goal is to provide effortless access to AI capabilities without requiring users to hop between separate platforms like ChatGPT, Perplexity, or Claude. Instead, everything is built into the browsing experience itself, making AI not just a tool—but part of the environment.
Built on the features above, Dia as a chat-and-AI-first browser can also learn from users' browsing history.
To turn it on:
Head to Dia > Settings > Early Access & toggle it on
When you want Dia to use history in your query, just tag @ History
For example: @ History what was that video I watched yesterday?
See it in action from @joshm below! https://t.co/JbmSJbY0CI— Dia (@diabrowser) June 11, 2025
It's worth noting that Dia is developed by The Browser Company, the same company that develops Arc.
These two products, despite promoting AI to an extent, they're actually distinctive, serving different purposes.
Whereas Arc is a design-focused browser with features like vertical tabs and a sidebar, aimed at rethinking traditional browsing. In contrast, Dia integrates AI deeply, offering horizontal tabs and chat-based navigation to streamline web use. While Arc emphasizes structure and productivity, Dia leans into AI-powered summarization and information extraction.
In turn, this should make web browsing a little more enjoyable.