Hi, this is probably a daft question…but I’m a newbie… so here goes! I introduced myself last week.
The Drone code specifies distances to keep away from people, buildings etc. But how do you know how far away your drone is from these potential hazards? I haven’t yet got a drone but I assume they don’t have a range-finder, at least for the cheaper models. I’m not sure I could manually estimate distances accurately!
Sorry if this is obvious, David
Pretty much just a guessing game, once you’ve flown a few times you will know roughly how far 50m is… therefore you will know how far roughly to stay away from people and buildings. 
Most drones even the cheaper ones do tell you distances although those distances are from you the pilot, not people and buildings around you.
Best of just playing it safe, and stay well away.
Use Google earth or Google maps, both have easy distance measure tools built-in I use them to take a look where I might be flying and use the measure to see how far it is to nearest road, train, buildings, etc.
If I’m posting a video from the flight, I sometimes import the kml file to Google earth and use the measure tool to make sure I kept my distance!
I think you may have misunderstood the question 
as a rough comparison guide football pitches are on average 50 metres wide an Olympic swimming pool is 50 metres long
handy if the park you fly from has pitches marked out
Distance from “other things/people” rather than from yoursef. 
The easiest way to judge distances is to listen to the reactions of the people around you:
50m = Overhead / dangerously close
150m = Nearly oerhead / dangerously close
In its carry case = About to be Overhead / dangerously close
Thanks everyone…great answers…and things to think about!
I’ve wondered before whether there would be any value in DJI (insert other drone manufacturer here) adding a range circle function to the app. E.g. a 50m overlay around your drone on the map which would allow you to assess distances at a glance.
Don’t over-think it. Other people can’t judge it better than you. 
Yeah sorry, having one of those fucking days 
But remember that most drones keep flight data. So if you do crash or bang on something, your insurance (or a court?) may ask to see it.
What people said is correct: you’ll learn to estimate better with practice.
What I’ve been doing is picking my spots where I go back to practice more. Then I check flight data and compare with Google Maps and similar tools. With every flight my confidence improves.
Thanks @felipe.
How easy is the process of checking flight data with Google maps/other tools? I’m in the process of purchasing a Mavic Air 2, so early days yet, but something I’d like to learn about.
Set up an account with airdata and connect that to DJI, quite straightforward. Your DJI logs are sync’d to airdata and airdata lets you download a kml file for each flight.
The kml file is a detailed log of your flight in a standard format which can be imported into Google earth, and other apps. Includes GPS data including position & altitude. You can then see where you have flown in Google earth.
Sounds great, thanks. I’ll look into this.
My simple advice. Find a location well away from people and buildings. I walk a very long way these days, big fields etc! Piece of mind and happy to be a safe pilot. Take off and keep your AC close, practice landing and RTH capabilities, just in case someone approaches from nowhere!
