About the Where Am I
Press the button and the browser asks the operating system where the device is, then hands back a latitude, a longitude and an accuracy radius in metres. On a phone outdoors that usually means GPS and a radius of a few metres. On a desktop it means a lookup of nearby wireless networks, or in the worst case the location of your internet provider, which can be tens of kilometres out. The accuracy figure is the honest measure of which of those you got.
Coordinates are shown twice: as decimal degrees, the form that map sites and spreadsheets expect, and as degrees, minutes and seconds, the form printed on paper charts and used by aviation and marine tools. Extra readings appear when the hardware supplies them, so a moving phone will also report altitude, speed in kilometres per hour and a compass heading. Five decimal places pin a point to about a metre, which is more than enough for a meeting spot; seven is beyond what consumer hardware can justify.
The reading never leaves the page. Map links are ordinary addresses that you choose to follow, and the geo: link hands the coordinates to whichever map app the device prefers. Turn on Keep updating to watch the position change while walking, which is the quickest way to see how much GPS drifts indoors. Browsers only allow this over a secure connection, and permission can be withdrawn at any time from the padlock menu.
How to use
- Press Show my location and accept the browser permission prompt.
- Read the latitude and longitude, and check the accuracy radius underneath.
- Follow a map link to see the point, or press Copy to paste it elsewhere.
- Tick Keep updating to follow the position live while you move.
Common questions
- How accurate is the position?
- It depends on the source. GPS outdoors is good to a few metres, wireless network lookup to tens of metres, and an address based estimate can be kilometres out.
- Does the page know where I am without permission?
- No. Nothing is read until you press the button and grant permission, and the answer is only ever shown to you on screen.
- Why does it say permission denied?
- The site was blocked for location, either now or on an earlier visit. Open the padlock menu in the address bar and allow location, then press the button again.
- What is the difference between decimal and DMS?
- They describe the same point. Decimal degrees suit software and spreadsheets, while degrees, minutes and seconds match printed charts and navigation instruments.