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    <p>Using just <code>SELECT * FROM Table WHERE lat between $minlat and $maxlat</code> will not be accurate enough.</p> <p>The correct way to query distance is using the coordinates in radians.</p> <pre><code>&lt;?php $sql = "SELECT * FROM Table WHERE acos(sin(1.3963) * sin(Lat) + cos(1.3963) * cos(Lat) * cos(Lon - (-0.6981))) * 6371 &lt;= 1000"; </code></pre> <p>Here is a handy reference - <a href="http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates" rel="nofollow">http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates</a></p> <p>For example: </p> <pre><code>&lt;?php $distance = 100; $current_lat = 1.3963; $current_lon = -0.6981; $earths_radius = 6371; $sql = "SELECT * FROM Table T WHERE acos(sin($current_lat) * sin(T.Lat) + cos($current_lat) * cos(T.Lat) * cos(T.Lon - ($current_lon))) * $earths_radius &lt;= $distance"; </code></pre> <p>And if you want to do the order by and show the distance:</p> <pre><code>&lt;?php $distance = 100; $current_lat = 1.3963; $current_lon = -0.6981; $earths_radius = 6371; $sql = "SELECT *, (acos(sin($current_lat) * sin(T.Lat) + cos($current_lat) * cos(T.Lat) * cos(T.Lon - ($current_lon))) * $earths_radius) as distance FROM Table T WHERE acos(sin($current_lat) * sin(T.Lat) + cos($current_lat) * cos(T.Lat) * cos(T.Lon - ($current_lon))) * $earths_radius &lt;= $distance ORDER BY acos(sin($current_lat) * sin(T.Lat) + cos($current_lat) * cos(T.Lat) * cos(T.Lon - ($current_lon))) * $earths_radius DESC"; </code></pre> <p>Edited for @Blazemonger and the avoidance of doubt :) If you want to work in degrees instead of radians:</p> <pre><code>&lt;?php $current_lat_deg = 80.00209691585; $current_lon_deg = -39.99818366895; $radians_to_degs = 57.2957795; $distance = 100; $current_lat = $current_lat_deg / $radians_to_degs; $current_lon = $current_lon_deg / $radians_to_degs; $earths_radius = 6371; $sql = "SELECT *, (acos(sin($current_lat) * sin(T.Lat) + cos($current_lat) * cos(T.Lat) * cos(T.Lon - ($current_lon))) * $earths_radius) as distance FROM Table T WHERE acos(sin($current_lat) * sin(T.Lat) + cos($current_lat) * cos(T.Lat) * cos(T.Lon - ($current_lon))) * $earths_radius &lt;= $distance ORDER BY acos(sin($current_lat) * sin(T.Lat) + cos($current_lat) * cos(T.Lat) * cos(T.Lon - ($current_lon))) * $earths_radius DESC"; </code></pre> <p>You could easily wrap this up into a class that accepted Radians or Degrees from the information provided above.</p>
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    1. POSorting MySQL query by Latitude/Longitude
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    1. COThat's more like it.
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    2. COI've my fair share of geo-location apps using this exact code. No complaints so far! :)
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    3. COLuke, I appreciate the answer but it's a bit confusing to me - could you edit it using my $max and $min variables in the correct places? I hate to ask but, well, you know :)
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