Point people to an exact spot, not a street address
Enter a latitude and longitude and this makes a code that drops a pin on that precise point in the reader's maps app — no address required. It's the answer for places a street address can't describe: a trailhead, a field gate, a festival entrance, a boat mooring, the far corner of a car park.
It encodes a geo: coordinate, which is the map equivalent of a phone number — a raw location the phone hands to whatever mapping app it prefers. Because it's coordinates and not a name, it lands on the exact metre you specify, not the rough centre of a postcode.
Which map app actually opens
The geo: link is generic, so the phone routes it to its default mapping app — Google Maps on most Android, Apple Maps on an iPhone unless Google Maps is set as default, and occasionally a prompt to choose. You can't force a particular app from the code; it hands the coordinate to the system.
In practice all the major apps accept the pin and offer directions to it. If a specific app matters, say so in text beside the code rather than expecting the QR to control it.
Latitude first, longitude second
Order matters and it's the easiest thing to get wrong. Latitude (north–south, roughly -90 to 90) goes in the lat field; longitude (east–west, -180 to 180) goes in the lng field. Swap them and your pin lands in the ocean or another continent.
A quick sanity check: in most populated northern-hemisphere places latitude is the smaller-magnitude, positive number. If your pin appears somewhere absurd, you've almost certainly transposed the two.
How many decimal places you need
Decimals control precision, and more isn't always better to type. Five decimal places pin you to about a metre — plenty for a doorway or a gate. Four gets you within roughly ten metres. Fewer than four and the pin drifts across a whole block.
- 3 decimals — ~100 m, only good for 'this village'.
- 4 decimals — ~10 m, fine for a building.
- 5 decimals — ~1 m, right for a specific door or gate.
- 6+ decimals — sub-metre, more precision than a phone GPS resolves anyway.
Getting clean coordinates to enter
Long-press the exact spot in a maps app and it shows the decimal coordinates to copy. Use decimal degrees (52.5200, 13.4050), not the degrees-minutes-seconds format with ° ′ ″ symbols — those don't belong in these fields and will produce a broken or misplaced pin.
How to make a location QR code
- Get decimal coordinates. Long-press the exact point in a maps app and copy the decimal figures. Avoid the degrees-minutes-seconds format — only plain decimals belong in these fields.
- Enter latitude in the lat field. The north–south value, between -90 and 90. Putting longitude here by mistake is the number-one reason a pin lands in the wrong hemisphere.
- Enter longitude in the lng field. The east–west value, between -180 and 180. Keep about five decimal places for metre-level accuracy at a door or gate.
- Scan and check the pin. Open it on a real phone and confirm the pin sits where you meant before printing — a transposed pair is obvious on the map.
Technical details
- Maximum characters: 2953
- Recommended error correction: M (medium) — a coordinate pair is a very short payload, so a balanced level already makes a bold, reliable code.
- Payload format: geo:<lat>,<lng> in decimal degrees — not degrees-minutes-seconds.
- Five decimal places give roughly one-metre precision; beyond six adds nothing a phone's GPS can actually resolve.
Frequently asked questions
- Which map app does the code open?
- Whichever is the phone's default — usually Google Maps on Android and Apple Maps on iPhone, sometimes with a chooser. The geo: link is generic, so you can't force one specific app from the code. All the major apps accept the pin and offer directions.
- Which comes first, latitude or longitude?
- Latitude first, longitude second. Latitude is the north–south value (-90 to 90) and goes in the lat field; longitude is east–west (-180 to 180) and goes in lng. Swapping them is the classic error and sends the pin to entirely the wrong place.
- How many decimal places do I need?
- Five gets you to about one metre — right for a specific door or gate. Four is within roughly ten metres, fine for a building. Three or fewer drifts across a block. More than six is pointless, since phone GPS won't resolve finer than that anyway.
- Can I use an address instead of coordinates?
- No. This type takes latitude and longitude only — that's its strength, since it pins an exact point an address can't describe, like a trailhead or a gate. If you'd rather share a named place, encode a maps link with the URL type instead.
- Why is my pin in the ocean?
- You've almost certainly swapped latitude and longitude, or entered degrees-minutes-seconds instead of decimal degrees. Re-check that the smaller-magnitude value is in lat, use plain decimals like 52.5200, and rescan — the pin should snap back to the right spot.
- Does it need internet to show the location?
- The scan reads the coordinates offline, but drawing the map and calculating directions needs a connection. The phone remembers the pin, so someone can scan it in a dead zone and get the route once they're back in signal.