September 18, 2026 · 6 min read · MapBench editorial
What Are Plus Codes? Open Location Codes Without a Street Address
Street addresses fail in the countryside, in new developments, and in cities where informal paths never got official names. Plus Codes (Open Location Codes) were designed as a workaround: a short string that encodes a grid cell on the Earth’s surface so anyone with a compatible map can find the same place. They are not a replacement for legal title or postal systems; they are a practical locator.
How a Plus Code behaves
A full global code stands alone. A shortened code is cheaper to say aloud but needs a surrounding city or region to disambiguate. Longer codes mean smaller cells — higher precision. Encoding is deterministic: the same coordinates yield the same code. That makes them useful in SMS, paper notes, and field teams that do not share a single proprietary map account.
- Good for: deliveries to unnamed plots, meeting points, asset tags
- Not for: proving ownership, replacing tax-parcel IDs, or ignoring local addressing laws
- Precision follows code length — do not demand door-level meaning from a short code
Plus Codes vs latitude/longitude
Coordinates are the underlying truth on WGS84. Plus Codes are a compact language for those coordinates. If a system accepts decimal degrees, you can always convert. If a person refuses to read negative numbers and decimal points over the phone, a code can be easier. Keep both when accuracy matters.
The toolkit behind this post, in depth
Plus Code Finder
Plus Codes are a compact way to encode a latitude and longitude into a short string that works without street addresses. They are especially useful where formal addressing is incomplete — rural areas, new developments, or informal settlements — and they can be shared in messages without special apps beyond a map that understands the code.
Encoding and decoding are deterministic: the same coordinates always produce the same full code, and shortening works relative to a reference area. Full global codes are longer; local shortened forms assume you already know the city or region. This tool converts both directions so you can paste a code from a delivery note or generate one from a map click.
Plus Codes are not a replacement for legal cadastral addresses. They locate a place on the WGS84 globe; property boundaries and postal routing still use official systems in most countries.
Latitude and Longitude Finder
This is the platform's universal coordinate picker: click or drag on the map and the panel instantly shows the point in decimal degrees, degrees-minutes-seconds, UTM zone/easting/northing, MGRS grid reference and Open Location (Plus) Code — each with its own copy button. Zoom controls the precision you can read, and five decimals already lands within about a metre. It is the page to keep bookmarked whenever another system asks 'what are the coordinates of this spot?'
Everything converts locally in your browser using standard WGS84 geodetic formulas, including the official Norway/Svalbard UTM zone exceptions, so the numbers you copy are interoperable with GPS devices, GIS software and mapping APIs. The current point lives in the URL, making any lookup shareable and reproducible — useful for property notes, field reports and support tickets. Pair it with the reverse geocoder when you also need the address, or feed the copied pair into distance, radius and elevation tools for deeper analysis.
Address to Coordinates
Geocoding is the forward direction of the address/coordinate bridge: type any address, landmark or place name and receive precise decimal latitude and longitude, pinned on the map and ready to copy into GPS devices, spreadsheets or API calls. Suggestions stream in as you type from the Photon geocoder, an OpenStreetMap-based service tuned for fast type-ahead search, so typos and partial addresses still land on the right feature. Each result shows its full disambiguation line — street, city, country — so 'Springfield' never silently picks the wrong state.
Typical jobs include programming a satnav, anchoring a delivery note, tagging a property listing, planning a meet-up, or seeding the distance and radius tools with exact endpoints. Because results are coordinates on the WGS84 datum, they drop directly into every other MapForge tool and into consumer GPS ecosystems. Accuracy follows the query: house-number addresses usually resolve within tens of metres, city queries to the settlement centre. The service is free and keyless for interactive use; for production-scale geocoding the fair-use notes on our data sources page explain how to stay a good citizen.
Coordinates to Address
Every coordinate pair describes one unique spot on Earth, but humans think in addresses. This tool bridges the two: paste any latitude/longitude pair — decimal degrees like 40.7128, -74.0060 or DMS like 40°26'46"N — and it returns the closest postal address, displayed both as a full line and as structured components you can copy individually. The map recentres on your point so you can visually verify the result before trusting it, which is exactly the workflow photographers, drone pilots, field scientists and delivery dispatchers need when reconciling GPS records with paperwork.
Because the conversion is powered by OpenStreetMap's Nominatim engine, coverage is worldwide and continuously improved by mappers: street-level detail in cities, settlement-level in remote regions. The tool validates your input first — latitudes beyond ±90 or longitudes beyond ±180 are rejected with a clear message instead of a silent wrong answer — and the resulting link stores your coordinates in the URL so a colleague can reopen the exact same lookup. Nothing is uploaded or stored server-side; the only outgoing request carries the coordinates you asked about.
Find My Location
Find My Location answers the simplest and most common map question of all: where exactly am I right now? When you press the button, your browser's built-in geolocation service combines GPS, Wi-Fi and cell-tower signals to estimate your position, and the page drops a pin on an interactive map at those coordinates. Immediately afterwards a single reverse-geocoding request translates the raw latitude and longitude into a readable address with street, city, county, state, postcode and country fields. You can copy any of these values, share the link, or jump straight into a related tool such as the county finder or the coordinate converter.
Privacy is the core design rule here. Your position is handled entirely inside your browser tab: nothing is written to a database, no account is involved, and the only network request carries the coordinates themselves to a public OpenStreetMap reverse geocoder. If you prefer not to share your position at all, you can click anywhere on the map instead and every feature keeps working. Accuracy typically ranges from a few metres outdoors with GPS to a few hundred metres indoors, where the browser falls back to network-based positioning.
The many languages of a single point
One physical spot on Earth can be written a dozen ways: decimal degrees for software, degrees-minutes-seconds for charts and handhelds, UTM eastings and northings for field work, MGRS lettered squares for military prose, Plus Codes for places without addresses. None is more 'true' — they are notations over the same WGS84 datum, the reference frame GPS itself speaks. Conversion between them is exact math, which is why it can run entirely in your browser with no service and no error creeping in.
The traps are human, not mathematical. Swapping latitude and longitude is the classic — GeoJSON stores [lng, lat] while most APIs expect (lat, lng), and an offshore point is usually that typo. Hemisphere letters and minus signs must never coexist. And precision has a physical meaning: each added decimal degree is roughly a tenfold shrink, so five decimals is about a metre, six is beyond what consumer GPS can claim. Choosing rounding deliberately is choosing honesty.
Datums are the deep end: coordinates are angles against a model of Earth's shape, and older local datums (NAD27 and friends) shift the same physical point by tens of metres relative to WGS84. A consistent, unexplained offset between an old survey and your GPS is usually that story. For everyday web mapping the datum is WGS84 end to end, and keeping everything in it — as these tools do — makes round trips exact.
Coordinate hygiene for people who reuse data
Coordinates are the one geographic asset that can be perfectly lossless — if you keep discipline. One datum (WGS84), one notation in storage (decimal degrees), one precision policy (five or six decimals), and conversions only at the display edge. Every deviation from that recipe taxes you later: mixed DMS strings in a column, NAD27 relics in an old shapefile, seven-decimal theatre in a CSV. The converters exist to absorb that variety at the border so your interior stays clean.
The second discipline is visual verification. A coordinate pair is two numbers; a pin on a map is a fact. Swapped axes, wrong hemispheres, degree/minute confusion — every classic error is instantly visible as a pin in the wrong ocean or the wrong hemisphere, and instantly invisible in a table. Professionals therefore make the map check a ritual: paste, look, then trust. At five decimals you are resolving metres; at that scale the eye, not the arithmetic, is the quality gate.
- Store decimal degrees, WGS84, signed; convert to DMS/UTM/MGRS only for the reader who needs them.
- Validate ranges on ingest (|lat| ≤ 90, |lng| ≤ 180) and reject, don't clip, out-of-range rows.
- Make the map-pin sanity check mandatory for any coordinate you didn't generate yourself.
- When receiving UTM or MGRS strings, record the original alongside the conversion — provenance prevents arguments.
Honest limits & when to escalate
Coordinates are lossless in principle and lossy in practice, and every loss is human: swapped axes, wrong hemispheres, datum relics, precision theatre. The converters eliminate the notation problem completely — DMS, UTM, MGRS and Plus Codes are exact translations on WGS84 — but they cannot eliminate the provenance problem: a number without its datum and its source is a rumour. Old NAD27-era documents, hand-typed sheets and seven-decimal CSVs each carry their own failure signature, and the honest tool answers with validation errors and visible pins rather than silent corrections.
The practical boundary is therefore organisational, not mathematical: teams that standardise storage (decimal, WGS84, sane precision) and ritualise the map check enjoy a lossless system; teams that don't accumulate expensive folklore. For work beyond consumer frames — control points, machine guidance, legal description — the escalation is geodetic: licensed surveyors, published transformations and national datums. Everything between a pasted waypoint and that door is exactly where this toolset lives.
- Datum-critical legacy data → published grid transformations (NTv2/HTDP).
- Control points and machine guidance → licensed geodetic survey.
- Aviation/marine charts → the chart's own datum and notation, verbatim.
- Massive pipelines → scripted validation with rejection, not clipping.
Step-by-step masterclass
- Standardise storage first — Decimal degrees, WGS84, five or six decimals in every column you own; convert at the display edge and the interior stays clean forever.
- Validate on ingest — Reject out-of-range values (|lat| > 90) instead of clipping; a rejected row is a fixable row, a clipped one is silent corruption.
- Make the pin check a ritual — Paste, look at the map, then trust — swapped axes and wrong hemispheres are instantly visible on a globe and invisible in a table.
- Match precision to source — Consumer GPS earns ~5 decimals; quoting more implies a survey you didn't run. Rounding deliberately is honesty.
- Preserve provenance — When converting UTM/MGRS strings, keep the original beside the decimal pair; provenance prevents every later argument about what was meant.
Notation culture splits by profession more than by country — mariners and aviators favour DMS and nautical frames, soldiers MGRS, developers decimals, hikers UTM — which is why a converter that shows all dialects simultaneously is more useful than any single 'correct' format.
Tips & common mistakes
Adopt one storage format — decimal degrees, WGS84, five or six decimals — for every dataset you own, and convert at the edges for display. Mixed notations in one column are the root of nearly every coordinate bug.
Sanity-check every pasted pair by eye on a map before using it: latitude/longitude swaps land you in the ocean so reliably that 'the Null Island bug' has a name. A two-second visual check costs nothing and catches most transcription errors.
Match precision to source: consumer GPS earns about five decimals; quoting six or seven implies a survey you didn't do. Rounding deliberately is honesty, not loss.
Quick glossary
- Datum: The reference shape model (WGS84 for GPS) that coordinates are angles against.
- DMS: Degrees-minutes-seconds notation; 1° = 60′ = 3600″.
- UTM: Metre-based zone/easting/northing grid on the WGS84 ellipsoid.
- Plus Code: Open Location Code: keyless short codes for any spot, by open math.
Two more questions, answered
Is MGRS usable at the poles?
Polar work switches to UPS; this tool covers the UTM domain where virtually all field grids live.
Why do some APIs want [lng, lat]?
GeoJSON follows the axis order of the OGC standard; remembering which world you're in prevents the ocean bug.