Coordinate Format Converter
Convert geographic coordinates between Decimal Degrees (DD), Degrees Minutes Seconds (DMS) and Degrees Decimal Minutes (DDM) — paste a latitude and longitude in any of the three formats and get all three side by side.
Input
Accepts Decimal Degrees, DMS, or DDM — format is auto-detected.
Accepts Decimal Degrees, DMS, or DDM — format is auto-detected.
Digits of decimal precision used for the Decimal Degrees output.
Output
| Format | Latitude | Longitude |
|---|---|---|
| No data yet | ||
Guides
What does this tool convert?
Geographic coordinates show up in three common notations, and they're rarely interchangeable at a glance:
- Decimal Degrees (DD) — a single signed number, e.g.
40.7128, -74.0060. This is what GPS chips, mapping APIs (Google Maps, Mapbox, GeoJSON) and most modern software expect. - Degrees Minutes Seconds (DMS) — the traditional surveying and navigation notation, e.g.
40°42'46.08"N, 74°0'21.6"W. Degrees are whole numbers, minutes and seconds subdivide each degree (60 minutes per degree, 60 seconds per minute), and a compass letter (N/S for latitude, E/W for longitude) replaces the sign. - Degrees Decimal Minutes (DDM) — a hybrid used by marine GPS units and search-and-rescue, e.g.
40°42.768'N, 74°0.36'W. Degrees stay whole, but minutes carry a decimal fraction instead of being split into seconds.
Paste a latitude and longitude in any one of these formats and this tool auto-detects which format you used — one number means DD, two means DDM, three means DMS — then shows the same point rendered in all three side by side.
When would I need each format?
- DD for plugging coordinates into code, spreadsheets, or a "paste into Google Maps" search box.
- DMS for aviation charts, land surveying documents, and older GPS/marine equipment that still reports in degrees-minutes-seconds.
- DDM for boating and handheld GPS units, which commonly default to decimal minutes as a middle ground between precision and readability.
How to use it
- Enter a latitude in the first field — decimal (
40.7128), DMS (40°42'46.08"N), or DDM (40°42.768'N) all work, with or without the compass letter. - Enter a longitude the same way.
- Pick a decimal precision (2–8 digits) if you need finer or coarser rounding — 6 digits is roughly 11 cm of precision, which covers nearly every practical use.
- Read the result table for the DD, DDM and DMS versions of your coordinate, or copy/download it as CSV.
Latitude must fall between -90° and 90°, and longitude between -180° and 180° — values outside that range (or text that can't be parsed as numbers) are flagged with a clear error instead of a bogus result.
FAQ
Why does my longitude show a negative sign in DD but a "W" in DMS/DDM? Decimal Degrees uses the sign to encode hemisphere (negative = South or West). DMS and DDM instead use a compass letter and always show degrees as a positive number — that's the traditional convention, so this tool follows it automatically based on the sign you entered.
Can I mix formats between latitude and longitude? Yes — enter latitude as DD and longitude as DMS (or any other combination); each field is parsed independently.
Does this tool store or transmit my coordinates? No. Conversion happens entirely in your browser — no location data is sent to any server.