# online mapping coordinate systems - what type are mine? **URL:** \ **Category:** Factual Questions\ **Created:** [March 4, 2012, 7:17pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739 "2012-03-04T19:17:50Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![ClarenceClancy](https://avatars.discourse-cdn.com/v4/letter/c/df788c/32.png) [@ClarenceClancy](https://boards.straightdope.com/u/ClarenceClancy)\ **Post date:** [March 4, 2012, 7:17pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/1 "2012-03-04T19:17:50Z")
i have coordinates like xxx,xxx.xxxx and y,yyy,yyy.yyyy but google maps doesn’t recognize them. Are these valid coordinates or maybe coordinates of a different sort that can be converted? ---
**Author:** ![chappachula](https://avatars.discourse-cdn.com/v4/letter/c/d2c977/32.png) [@chappachula](https://boards.straightdope.com/u/chappachula)\ **Post date:** [March 4, 2012, 7:47pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/2 "2012-03-04T19:47:12Z")
There are many, many different coordinate systems. Every country has its own grid,and every state in the US has its own grid. Where are you? Where did you get your xxx, yyy numbers? Check the source. There’s usually a small note on the map (maybe somewhere down around the copywrite date) that specifies which grid is used. ---
**Author:** ![ClarenceClancy](https://avatars.discourse-cdn.com/v4/letter/c/df788c/32.png) [@ClarenceClancy](https://boards.straightdope.com/u/ClarenceClancy)\ **Post date:** [March 4, 2012, 7:53pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/3 "2012-03-04T19:53:51Z")
> [@chappachula](#): > > There are many, many different coordinate systems. > Every country has its own grid,and every state in the US has its own grid. > > Where are you? > Where did you get your xxx, yyy numbers? Check the source. There’s usually a small note on the map (maybe somewhere down around the copywrite date) that specifies which grid is used. This is from a ‘construction table’ on a blue print from a licenser in Mexico. Has someone created a listing of all the grids online that you know of? If so, I could try each one, and then maybe find a converter for google’s system. ---
**Author:** ![Jaguars](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jaguars/32/5879_2.png) [@Jaguars](https://boards.straightdope.com/u/Jaguars)\ **Post date:** [March 4, 2012, 8:45pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/4 "2012-03-04T20:45:26Z")
Check the notes section of the plan, looking for anything that metions coordinates, datums or grids. Any draughtsman should put that info in his plans. If they haven’t, you will just have to contact them and ask. I don’t know North american systems, but according to the Wiki some that might be available are: North American Datum of 1983 (NAD 83) World Geodetic System (WGS84) Universal Transverse Mercator (UTM) and also the arbitrary site grid. (Everything is relative to a marker on the building site) Apart from those, there will be dozens of other local ones so it’s unlikely there will be a complete list. to give you an idea of just how many there could be, check out [this](http://apps.linz.govt.nz/coordinate-conversion/?advanced=1) NZ site. (note that lots of these ones are obsolete) ---
**Author:** ![newme](https://avatars.discourse-cdn.com/v4/letter/n/e0b2c6/32.png) [@newme](https://boards.straightdope.com/u/newme)\ **Post date:** [March 4, 2012, 10:34pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/5 "2012-03-04T22:34:26Z")
Those look like UTM coordinates. The first number is the easting, the second is the northing. Without knowing the UTM zone, we can’t convert those to latitude,longitude. There is a UTM converter here: [http://leware.net/geo/utmgoogleapp.htm](http://leware.net/geo/utmgoogleapp.htm) What is the approximate location, in degrees west longitude? ---
**Author:** ![Reply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/reply/32/15952_2.png) [@Reply](https://boards.straightdope.com/u/Reply)\ **Post date:** [March 4, 2012, 10:45pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/6 "2012-03-04T22:45:30Z")
If you don’t have ready access to geographic information system software, you can try something like this free [geographic translator](http://earth-info.nga.mil/GandG/geotrans/) and just try converting between different potential projections until you get one that seems to make sense in Google Maps. Note that there are some coordinate systems that are close enough that an incorrect guess could still seem correct, and you won’t notice the errors until you examine more points… so depending on what you need to do with the information and whether you can correlate all points to known landmarks, this may or may not be a sound method. ---
**Author:** ![ClarenceClancy](https://avatars.discourse-cdn.com/v4/letter/c/df788c/32.png) [@ClarenceClancy](https://boards.straightdope.com/u/ClarenceClancy)\ **Post date:** [March 4, 2012, 11:48pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/7 "2012-03-04T23:48:59Z")
> [@newme](#): > > Those look like UTM coordinates. The first number is the easting, the second is the northing. Without knowing the UTM zone, we can’t convert those to latitude,longitude. > There is a UTM converter here: [http://leware.net/geo/utmgoogleapp.htm](http://leware.net/geo/utmgoogleapp.htm) > What is the approximate location, in degrees west longitude? Talking about the North/South line intersecting Las Vegas. Which UTM zone does that result in? ---
**Author:** ![newme](https://avatars.discourse-cdn.com/v4/letter/n/e0b2c6/32.png) [@newme](https://boards.straightdope.com/u/newme)\ **Post date:** [March 5, 2012, 1:05am UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/8 "2012-03-05T01:05:13Z")
Las Vegas is in UTM Zone 11, which runs from 120 to 114 degrees West. Between 32 and 40 degrees North, use 11 S. Between 24 and 32 degrees North, use 11 R. Between 16 and 24 degrees North, use 11 Q. ---
**Author:** ![newme](https://avatars.discourse-cdn.com/v4/letter/n/e0b2c6/32.png) [@newme](https://boards.straightdope.com/u/newme)\ **Post date:** [March 5, 2012, 2:20am UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/9 "2012-03-05T02:20:45Z")
Do those coordinates from the map actually have 4 decimal places? UTM coordinates are in meters. Four decimal places implies better than millimeter accuracy, so maybe UTM is not the answer after all. ---
**Author:** ![Edward\_The\_Head](https://avatars.discourse-cdn.com/v4/letter/e/ce73a5/32.png) [@Edward\_The\_Head](https://boards.straightdope.com/u/Edward_The_Head)\ **Post date:** [March 5, 2012, 3:04am UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/10 "2012-03-05T03:04:05Z")
You could have some sort of state coordinate system as well. They usually start in a point to the south west, even outside of the state, so that all points in the state are positive. As a few others have said the map you have should have some sort of note saying what the system is. ---
**Author:** ![Mr\_Downtown](https://avatars.discourse-cdn.com/v4/letter/m/8e8cbc/32.png) [@Mr\_Downtown](https://boards.straightdope.com/u/Mr_Downtown)\ **Post date:** [March 5, 2012, 4:31am UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/11 "2012-03-05T04:31:51Z")
Why do people feel they need to be so anonymous and _mysterious?_ If you can give the actual numbers (change around a couple of the last digits if you want) and some hint of the city you expect them to be in, it will be a lot easier for us to guess. I would say it’s probably a state plane coordinate system, in feet. ---
**Author:** ![ClarenceClancy](https://avatars.discourse-cdn.com/v4/letter/c/df788c/32.png) [@ClarenceClancy](https://boards.straightdope.com/u/ClarenceClancy)\ **Post date:** [March 5, 2012, 6:27pm UTC](https://boards.straightdope.com/t/online-mapping-coordinate-systems-what-type-are-mine/614739/12 "2012-03-05T18:27:05Z")
Thanks guys, I found a site ( [http://users.tpg.com.au/adslly6v/UtmGoogleStreetView.html](http://users.tpg.com.au/adslly6v/UtmGoogleStreetView.html) ) and used newme’s zone 11 and got my coordinates. I think they might be Clarke 1866 coordinates.