Is there any data on how much time developers spend looking stuff up?

According to some studies between 58% and 68% of their time

https://blog.feenk.com/developers-spend-most-of-their-time-f...

Not really, but as an Android developer, it's a ton. Maybe 80% of the work (including the dread and procrastination). The documentation is pretty bad, or incomplete. Stack Overflow used to be a good substitute for documentation, but it's hostile to all new questions, so the new stuff isn't really covered. I'm considering doing some open source documenting to help make up for this but I suppose none of us could spare the time.

For me there are a bunch of different kinds of looking stuff up as well. It’s almost all valuable though.

Sometimes there’s highly specific - reading the docs.

Sometimes it’s adjacent or wildly different technology/concepts.

Sometimes it’s thinking about a side project or making a toy piece of software to try something out, and the reading that goes into learning how to do that.

Equally just browsing HN and others.

I find there’s a lot of learning by osmosis that’s necessarily not measurable/quantifiable.

I spend a lot of time looking stuff up. It's just that most of it is not relevant to development.

As an expert in the system, I've done very little research - maybe 1 hour per day helping others troubleshoot. As a new guy in the system or as a security resource, I've done a lot - maybe 3 hours per day.

I don't have official number, but join the "a lot" vote.

I am not sure if you'll find a good correlation to developer or area experience, at least by my personal experience people offload memorizing of stuff to Google search

Anecdotally, a lot, and not enough.