Coordinates Converter

How to use the coordinates converter

What this calculator does

This calculator rewrites one geographic latitude/longitude pair in three common notations: decimal degrees (DD), degrees – minutes – seconds (DMS), and degrees with decimal minutes (DDM). It is useful when a GPS receiver, map, survey note, photo record, or data system expects a different notation from the one you have. The conversion changes only how the angular values are written; it does not move the point, identify its map datum, or convert it into a projected grid such as UTM.

When to use it

Use it to copy a phone's decimal coordinates into a DMS field, translate a field notebook's DMS reading for a spreadsheet, compare coordinates supplied in different formats, or prepare a consistent latitude/longitude pair for a mapping workflow. For higher-accuracy geodetic work, first confirm the coordinate reference system and datum with the receiving application.

How to calculate

1. The calculator opens with a complete Sydney-area demonstration in DD, and its Excel workbook is immediately available.
2. Select Decimal degrees (DD), DMS, or DDM under “I have the coordinates in...” to match your source.
3. Replace the latitude and longitude values. Results update live in all three formats.
4. Read the combined DD result, the DMS result, the DDM result, and the row-by-row format comparison.
5. Choose Download Excel to save the current inputs and conversions as a validated .xlsx workbook.
6. Choose Reset to clear the demonstration and all computed output. Excel export remains unavailable until a complete valid pair is entered again.

Input guide

Latitude (decimal degrees) and Longitude (decimal degrees) accept plain base-10 numbers using a period as the decimal separator. Latitude is required from – 90 through 90; longitude is required from – 180 through 180. A negative latitude means south and a negative longitude means west. Example: – 33.858611, 151.214167. Do not add degree symbols, direction letters, thousands separators, or scientific notation to DD fields.

In DMS mode, latitude and longitude each use a nonnegative degrees value, whole minutes from 0 through 59, decimal seconds from 0 up to but not including 60, and a direction. Latitude degrees may not exceed 90, longitude degrees may not exceed 180, and minutes/seconds must be zero at the maximum degree. A common mistake is entering a negative degree while also choosing S or W; directions carry the sign in DMS mode.

In DDM mode, each coordinate uses nonnegative degrees, decimal minutes from 0 up to but not including 60, and a direction. As with DMS, values at exactly 90° latitude or 180° longitude must have zero minutes. Example: 33 degrees, 51.516660 minutes, S. Changing any component changes the same underlying decimal-degree value and all outputs.

Output guide

Decimal degrees (DD) is the signed numeric pair, always latitude first and longitude second. Degrees, minutes, seconds (DMS) expresses each absolute angle with a cardinal direction. Degrees, decimal minutes (DDM) keeps whole degrees and decimal minutes. The hemispheres pill summarizes direction, the input format pill identifies the active source notation, and the precision pill records the displayed DD precision. Every output is an exact notation conversion subject only to displayed rounding; it is not a location recommendation or datum transformation.

Worked example

The startup latitude is – 33.858611 and longitude is 151.214167. For latitude, the absolute degree value is 33. The remainder, 0.858611, multiplied by 60 gives 51.516660 minutes. Keeping 51 whole minutes and multiplying the remaining 0.516660 by 60 gives 30.9996 seconds, displayed as 31.000 seconds. Because the original latitude is negative, its direction is S. The longitude becomes 151° 12′ 51.001″ E. Therefore the first-open DMS output is 33° 51′ 31.000″ S, 151° 12′ 51.001″ E.

The underlying identity is explained by the FCC's DMS and decimal-degree conversion guide, while NOAA's NGS coordinate conversion tool illustrates why notation and datum transformation are distinct tasks.