Find Previously Visited Websites in Seconds

You only remember words from the text of a website, but not from the title? Full-Text Search the pages & PDFs you visited and bookmarked.

As seen on

Click to download


Full-text search websites & PDFs you visited and bookmarked

Remember that one article with the words "climate change" in the text? You can't search like that in your brower's history or bookmarks. Search for every word you remember.

Import your your existing history and bookmarks

By default, the Memex indexes everything you visit after installing it. You can import your existing browsing history and bookmarks.

Blacklist Domains & Urls

Prevent entire domains from being indexed when you visit them and retrospectively delete unwanted websites with ease. Use simple URL fragments or complex RegExp.


What happens with my data?

All your personal data is stored on your computer.
We, or anybody else, will never have access to it by default.
Later, you can proactively share it with others, which is part of our long-term vision

The only data that is sent to us, are some basic, anonymised usage statistics about how people use the extension. You can always opt-out from that. More you can read in our privacy policy

How do you make money?

Right now we are funded by personal investments of the founder Oliver Sauter and a grant by Digital Science

Soon, we are launching our cloud support premium service. 
It will enable users to have:

  • an encrypted backup of your data in the cloud
  • search and index websites from their mobile phones, the web or other browsers.
  • better search features, that are technically not possible in the browser (like image search)
  • speed improvements, because you can offload storage and computation resources into the cloud. (e.g. faster background import of your browsing history, bookmarks and other services=
  • sharing (collections of) links and other data with friends, colleagues and followers, even if you are not online
Users with knowledge of how to run and maintain a server we will provide with the software to completely self-host their data.
How much computer resources does Memex need?

Per url visited it stores on average around 140kb. If you are a heavy web user with 30.000 visited documents you end up with about 4GB of data per year. With our premium offering you can offload this to the cloud, if you wish.  

While being idle, the extension needs around 80MB of Ram, which can go up to about 250-300 when you are opening the search overview or settings. Only when importing your previous history or bookmarks, the extension gets demanding. 

Only when you are using the importer for your history & bookmarks, or about 10-15seconds after you visit a website the CPU spikes a bit because of the resources needed to index pages. 
With weaker machines you might experience a lag. We are constantly working on performance improvements. With our upcoming premium service, you can offload most of that work to the server. 

Our Vision

At WorldBrain, we work towards a scalable and sustainable solution to misinformation. Doing so by creating a collaborative search engine by enabling you all to connect your Memexes with each other. In this network, you'll be able to effortlessly exchange the most useful content and important contextual information you found in your web-research