On OSX, I wrote an installable startup daemon that logs the current window, and for browsers, captures the URL from the address bar, and logs it to a file. The sampling can be whatever period you decide, but you have to write your own analytics. I haven't made it generally available, but it was a pretty quick project to capture the basic data.

Here's the basic outline:

* Bash script that uses lsappinfo front to figure out what has focus * log the time, the app name, and other useful data

* If the current app is a browser, then branch on the browser type and "return URL of" the front tab or current document depending on the browser

* Echo whatever you want to capture to STDOUT

Then write up a startup .plist file to install and log the output.

https://timingapp.com seems to fit the bill, it’s a local app for os x with optional sync capabilities

I used the free trial when it first came out, it's pretty slick.

I use https://github.com/Naereen/uLogMe (it's a fork of a tool Andrej Karpathy wrote a few years ago: http://karpathy.github.io/2014/08/03/quantifying-productivit...). It collects data on your general computer usage by measuring the active time and amount of keystrokes per window. It has two parts: some scripts to collect the data and a web interface to visualize the data.

The main drawback of such tools is that most ot them seem to require X11 and won't work with wayland.

Similar tools: https://github.com/ActivityWatch https://flowdash.co

If you use Firefox, there's a local file called places.sqlite that stores history, queries, bookmarks, etc.: http://kb.mozillazine.org/Places.sqlite

ManicTime and Leechblock are two solutions that work entirely locally, on Windows.

Edit: I meant with free/opensource software and possibly on linux.