From grid locator to distance
Grid locator and distance: convert your Maidenhead QTH locator to coordinates and back, work out distance and beam heading to another station and see the path on a world map and on an azimuthal map centred on you.
Locator ↔ coordinates converter i
Your data stays in your browser. The “Use my location” button asks the browser for permission only when you press it and sends nothing to RadioMeteo.
i
Your data stays in your browser. The “Use my location” button asks the browser for permission only when you press it and sends nothing to RadioMeteo.Enter a locator (e.g. JN62wo) or coordinates in decimal degrees (42.604, 13.875) or in degrees and minutes (42°36'N 13°52'E).
Distance and heading between two stations i
Short path: WGS84 ellipsoid using Vincenty’s method. Long path: mean Earth circumference minus the short path, an approximate value (difference below 0.5 %). Locators use the centre of the square: more characters, more precision.
i
Short path: WGS84 ellipsoid using Vincenty’s method. Long path: mean Earth circumference minus the short path, an approximate value (difference below 0.5 %). Locators use the centre of the square: more characters, more precision.Enter two locators or two pairs of coordinates. You get short-path and long-path distance, and the beam heading from A to B and back.
Path maps i
Natural Earth vector mapping (public domain), with no roads or photos. The azimuthal map shows the whole globe: its outer edge is the antipode of station A.
i
Natural Earth vector mapping (public domain), with no roads or photos. The azimuthal map shows the whole globe: its outer edge is the antipode of station A.Left: the great circle on a world map. Right: an azimuthal equidistant map centred on station A, where every direction is a true heading and distances from the centre are to scale.
Calculate a distance to see the path.
How the Maidenhead locator works
The locator divides the globe into ever smaller rectangles. It comes from a meeting of European VHF managers in Maidenhead, England, in 1980, and is now used worldwide.
| Characters | Level | Values | Size |
|---|---|---|---|
| 1–2 | Field | Two letters A–R | 20° × 10° |
| 3–4 | Square | Two digits 0–9 | 2° × 1° (about 160 × 110 km in Italy) |
| 5–6 | Subsquare | Two letters A–X | 5′ × 2.5′ (about 7 × 4.6 km) |
| 7–8 | Extended square | Two digits 0–9 | 30″ × 15″ (about 700 × 460 m) |
In VHF and higher contests the 6-character locator is part of the exchange and scoring often depends on distance; awards count the different squares worked. By convention the last two letters are written in lower case (JN62wo), but upper and lower case mean the same.
Sources: ARRL — Grid locators, Natural Earth, Geoscience Australia — Vincenty inverse. Sources consulted on 18 October 2026. Links open on the publisher’s website.
Grid locator and distance in practice
Pointing the antenna
The calculated heading refers to true north. With a rotator calibrated on true north you set the value directly; with a compass you must correct for the magnetic declination of your area.
Long path
When the short path is closed, on HF the signal may arrive from the opposite side, especially at dawn and dusk along the grey line: then point the antenna at the long-path heading.
VHF and UHF contests
In VHF, UHF and higher contests scoring is often in kilometres, computed from the 6-character locators exchanged in the QSO: the calculator tells you at once what a contact is worth.
How precise it is
A 6-character locator gives the centre of a rectangle of about 7 × 4.6 km: for short distances, under 50 km, the error can matter. In that case use coordinates or the extended 8-character locator.
See also: Satellites and ISS · WebSDR receivers and beacons · Logbooks, QSL and awards · Radio lab tools
Articles on locators, distances and VHF contests
RadioMeteo articles about locators, distances and VHF/UHF activity appear here automatically when they are published.
There are no articles on this topic yet.