Geodesic Distance Calculator
This calculator only currently works when the NSEW directionality on both latitudes and on both longitudes match. For example, pairs (30.1N,75.6E) and (30.4N,70.2E) should yield an approximately correct result, but (30.1N,75.6E) and (30.4N,70.2W) will not.
This implementation uses the Halversine central angle formula and outputs results in standard miles.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Copyright 2012 by Reed McGrew under the MIT License