So I flew my Mini 4 Pro yesterday for the first time from a 2nd floor balcony. I ran two tests to see how high I could go and was surprised how low 400 ft actually is. I thought 400ft would be like the height of a 40-foot building! Does anyone else think the altitude readings might not be accurate? Maybe I should tie a 400ft rope to check 
The drone measures height from where you took off, and you took off from a 2nd floor balcony. Think about that. Also, a 40-foot building isn’t 400ft, it’s 40 feet. Maybe you meant a 40-story building, which is usually taller than 400ft.
400 feet is 400 feet. Not sure what else to say.
400 ft really is 400 ft. How old are you that you don’t know how far that is?
More like 30 stories tall. DJI drones are pretty accurate: my Avata 2 shows exact altitude with sensors and lands within 0.3m on return home. 400 ft gives an amazing view. Also reminds me of a joke… link
If you’re doubting the altitude reading, did you wait for satellite confirmation before flying? Some people don’t and that can mess up data. But honestly, 400 ft is what it says. I don’t see why the DJI app would be wrong.
Not sure what country you’re in, but in the US the max height is 400 feet above ground level where you took off. So if you took off from a balcony, the drone measures height from there. If you want to measure a building’s height, take off from the ground next to it. Usually buildings over 30 stories are taller than 400 feet.
@Noe
To add, you can’t take off from the 2nd floor and expect the reading to be from the ground up to the top of the building. The reading is always from where you took off. So 400 ft isn’t that high when you think about tall city buildings.
The drones can go higher, but after updates they usually limit you. I’ve had some older models that would fly way higher until signal cut out. Just fly safely, watch out for air traffic, and use a flight app. No real reason to push it super high unless you just want to see how far it’ll go.
No offense, but this reminds me of this video
“Maybe I should attach a 400ft rope to check ” I get the memes about DJI owners now. Haha.
One foot isn’t very big, to be fair.
Not sure you can keep the drone in sight at 400 ft with a Mini 4 Pro. I can barely see my Mini 2 SE at around 250-300 ft above ground.
Sage said:
Not sure you can keep the drone in sight at 400 ft with a Mini 4 Pro. I can barely see my Mini 2 SE at around 250-300 ft above ground.
Depends on the day. I can see my M4P at 400 ft straight up, but not if it’s 400 ft away unless the sky is clear and blue. Overcast, no chance to spot it.
@Keaton
And here I am stuck waiting for a break in the rain to get a quick shot at a worksite on this drizzly day. Getting everything ready to try and grab the images before heading back to the office.