How much does my location permission give away?

Your phone can give an app your exact spot or only a rough area. See how much each extra digit of a location narrows it down, and what your phone lets you choose.

Digits after the decimal point

45.51, -73.56

Narrows it to about 3,600 feet

A demo point in Montréal, not your location. One degree of latitude is about 69 miles (364,000 feet), says the US Geological Survey; each extra digit divides that by ten.

What your phone lets you choose

iPhone: Never, Ask Next Time Or When I Share, While Using the App, or Always. To share only an approximate location, turn Precise Location off. Apple gives no distance for “approximate”.
Android: Allow all the time, Allow only while using the app, Ask every time or allow when you share, or Don't allow. Android's developer guide says approximate location is accurate “to within about 3 square kilometers (about 1.2 square miles)”, and precise location “usually within about 50 meters (160 feet)”.

What location data has revealed

August 2022: the FTC sued the data broker Kochava, saying its location data “can reveal people's visits to reproductive health clinics, places of worship, homeless and domestic violence shelters, and addiction recovery facilities”.
January 2024: the FTC took action against X-Mode Social and Outlogic, the company that took over most of its operations, saying X-Mode sold location data “that could be used to track people's visits to sensitive locations such as medical and reproductive health clinics, places of religious worship and domestic abuse shelters”.
2013 research: in phone-network records of 1.5 million people over 15 months, “four spatio-temporal points are enough to uniquely identify 95% of the individuals”. The locations were only as precise as the phone company's antennas, once an hour.

Sources (7)Where each fact comes from