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I can't seem to get the measure tool to match up with my distance matrix tool regardless of what measurements I use. There are conflicting answers on other posts about this question. Both of my layers are on WGS84

PolyGeo
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tonysdatamodels
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    Please provide links to the "other posts about this question" that you mention so that we can try to improve any content in them that is "conflicting". – PolyGeo Jan 15 '20 at 23:23
  • gis.stackexchange.com/questions/20291/what-are-the-units-of-the-distance-matrix-tool-results-in-qgis – tonysdatamodels Jan 15 '20 at 23:32
  • Please use the [edit] button beneath your question to revise it with any requested clarifications. – PolyGeo Jan 15 '20 at 23:33

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Typically, most tools in a GIS will calculate distances in the units of the coordinate system. If they're WGS84, I suggest it's calculating distances in degrees which is nonsensical. I suggest projecting your data to a projected coordinate system which has units in metres or feet, depending on your local standard.

Fezter
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  • Thanks Fetzer. Can I ask why it is nonsensical? For example is there any way of converting degrees to KM ? Or are the 2 things relative to eachother at all? – tonysdatamodels Jan 15 '20 at 23:18
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    One degree on west-east direction along the equator is 111 km while on the top of the North Pole the distance is 0 meters. Converters exist, for example https://www.nhc.noaa.gov/gccalc.shtml. – user30184 Jan 15 '20 at 23:23
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    It's non-sensical because degree distances change on a sphere. Think of lines of longitude converging at the poles. The distances between them get smaller as you approach the poles. I won't answer your other questions in the comments as there are other posts on this site which answer them. I really do suggest you convert your data to a projected coordinate system first and try again. – Fezter Jan 15 '20 at 23:24