What is DDM coordinate format?

Degrees and decimal minutes keeps whole degrees and expresses the remainder as decimal minutes. For example, 46.5 degrees north is 46 degrees 30.0000 minutes north.

Does DD, DMS, or DDM conversion change the datum?

No. Reformatting angular values does not transform NAD27, NAD83, WGS84, datum realizations or epochs, UTM, State Plane, altitude, or a projected coordinate system.

Why can coordinates from an old map disagree with GPS?

The sources may use different datums, coordinate systems, measurement methods, or accuracy. Preserve the source coordinate reference, datum, method, and uncertainty.

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Latitude Longitude Coordinate Converter

Convert one geographic coordinate pair among decimal degrees DD , degrees–minutes–seconds DMS , and degrees–decimal-minutes DDM . Latitude is shown first and longitude second. Valid latitude extends from 90 degrees south to 90 degrees north; valid longitude extends from 180 degrees west to 180 degrees east. In sexagesimal notation, minutes and seconds are at least zero and less than 60. To convert DMS to decimal degrees, add degrees, minutes divided by 60, and seconds divided by 3,600, then make South and West negative. To convert decimal degrees to DMS, retain whole degrees, multiply the fractional remainder by 60 for minutes, and multiply the remaining minute fraction by 60 for seconds. DDM retains whole degrees and uses decimal minutes. GeoMiner performs arithmetic locally in the browser and does not send the coordinate to GeoMiner or a third-party map. Analytics retain only bounded action and input/output format categories—never latitude, longitude, degrees, minutes, seconds, hemisphere, datum, coordinate reference system, project, station, route, place, or notes. Formatting is not a coordinate transformation. Writing the same angles as DD, DMS, or DDM does not convert NAD27 to NAD83 or WGS84, change a datum realization or epoch, project latitude and longitude into UTM or State Plane, convert elevation, infer a map projection, or establish a coordinate reference system. A datum mismatch can move the apparent point by tens or hundreds of metres. Preserve the original coordinate string, axis order, horizontal datum and realization, epoch where relevant, vertical datum, source map or dataset, acquisition method, equipment, accuracy, station identifier, and uncertainty. Precision is not accuracy: extra decimal places cannot improve the source receiver, map, imagery, digitizing, georeferencing, satellite geometry, multipath, canopy, terrain, or control. Check whether an importing system expects latitude–longitude, longitude–latitude, northing–easting, or x–y before using a result. At poles and the antimeridian, more than one written longitude or hemisphere convention may describe the same physical place. This converter intentionally does not guess a datum, transform a CRS, convert UTM, or claim survey-grade accuracy. Consequential exploration, claim, boundary, engineering, navigation, environmental, legal, or emergency work requires verified source metadata,

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Verification resources

Cross-check terminology, classification, methods, and safety with these authoritative external resources.

undefined. Latitude and longitude degree, minute, second, hemisphere, range, and precision conventions.
undefined. Why coordinates must retain their horizontal datum, realization, epoch, and related reference information.
undefined. NAD27, NAD83, and WGS84 context and the warning that a datum mismatch can move a plotted position.
undefined. Latitude/longitude and UTM are different ways of positioning a point; UTM includes 60 six-degree zones.
undefined. Official coordinate reporting with integer degrees, integer minutes, decimal seconds, and hemisphere identifiers.

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Common questions

How do I convert degrees, minutes, and seconds to decimal degrees?: Use degrees plus minutes divided by 60 plus seconds divided by 3,600, then make South and West negative. Minutes and seconds must each stay below 60.
How do I convert decimal degrees to DMS?: Keep the whole-number degrees, multiply the decimal remainder by 60 for minutes, and multiply the remaining minute fraction by 60 for seconds. Negative latitude is South and negative longitude is West.
What is DDM coordinate format?: Degrees and decimal minutes keeps whole degrees and expresses the remainder as decimal minutes. For example, 46.5 degrees north is 46 degrees 30.0000 minutes north.
Does DD, DMS, or DDM conversion change the datum?: No. Reformatting angular values does not transform NAD27, NAD83, WGS84, datum realizations or epochs, UTM, State Plane, altitude, or a projected coordinate system.
Why can coordinates from an old map disagree with GPS?: The sources may use different datums, coordinate systems, measurement methods, or accuracy. Preserve the source coordinate reference, datum, method, and uncertainty.

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Latitude Longitude Coordinate Converter

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Verification resources

Common questions