Welcome to Geochecker, a simple tool to check coordinates for geocaching puzzle caches.
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How do I change the coordinates for a link to my geocache?
You have two options if you wish to relocate your geocache or change the coordinates. Once you create a link, the coordinates are encoded within the link itself. So (option 1) you can simply create a new link and stop using the old one. However, you may have a good reason to keep using the same link - maybe you published it on a blog, for example. In that case, (option 2) you can sign up for GeoChecker+, a service we offer for a small annual cost. For links on your GC+ account, you can specify which coordinates are accepted, as well as customizing the link checking page and the correct response page, and much more. GC+ users also don't have to see any ads on our pages.
As the cache owner, once you create a link, you'll get a special code you can use to get some VERY BASIC statistics about your puzzle. The stats are limited to how many people have visited your puzzle's checking link, and how many good and bad solutions were attempted. If you wish to allow people to use this link, you may. We also give you an extra-special code that tracks the guessed coordinates for a given link - it's not directly tied to your cache in any way, so it can't be used to find your cache. Also, only you can see this info, not your cache seekers. And we log usage statistics so we can prevent hacking attempts and keep an eye on things. That's it. That is the sum total of the data we collect. We do not log coordinates that you enter for your puzzle. We don't collect, ask for, or log any personally-identifiable information, at all.
In case you're wondering if this tool is secure, not to worry. This script was designed to prevent reverse-engineering the coordinates. It uses a "one-way" hash, a code that is highly unique to that data. However, it does not actually contain the data, encoded or otherwise. This means that it is literally impossible to determine the coordinates from the stored link. The only way to attack it is brute strength - trying every possible combination of coordinates until the solution is presented. Considering there are approximately 2.8 million unique coordinates in a one mile radius, that would be a lot of trying!
A hacker might also try to crack it on a home computer - but he would have no idea what data goes into the hash, how the coordinates are encoded, etc. It would be improbably difficult to crack - in fact, the easiest solution is just to solve the puzzle posed by the cache owner!
Most people only experience this issue when they are trying several solutions in a row. Usually this is caused when you use the Back button on the browser, which then shows you the last security code. However, the security code can only be used once (that's why it's secure!). So if you see the same five characters as the previous code, you will need to use the Refresh or Reload button on your browser to ensure that you have a fresh code each time you try a solution.
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What about "fuzzy" solutions? How do they work?
When a cache owner creates a link, they have the option to specify either an exact solution or a "fuzzy" solution. If it's Exact, then the coordinates that a puzzle solver enters must precisely match the puzzle's solution coordinates. If it's Fuzzy, then as long as the proposed solution is within the owner's allowed distance, a successful result will be shown.
There are two "fuzzy" ranges currently offered:
+25 ft or 8m; the actual range is plus or minus 0.005 minutes.
+100 ft or 30m; the actual range is plus or minus 0.017 minutes.
As an example, for the fuzzy 25 foot / 8m solution, if the actual coordinates were N38 10.135 W76 20.195, any North solution from N38 10.130 to 10.140 would match, and and any West solution from 76 20.190 to 20.200 would match. Please notice that this is a SQUARE of possible solutions - it's not a radius. So you could be 35 feet / 11m away on a diagonal.
When a puzzle solver hits the coordinates exactly, even if fuzzy solutions are allowed, they will get a normal success message. But for fuzzy cache solutions (NOT for exact solutions) if the solution is off by even 0.001 minutes in any direction, then Geochecker will inform the solver that they're close (somewhere within the allowed range) but not exactly on target.
Please notice that the Google Maps link and the Success coordinates will match the proposed solution that the solver enters - we don't give away the exact solution in the Success message.
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I created a link before you allowed "Fuzzy" solutions. Can I change a solution from Exact to Fuzzy?
No problem. Just recreate the link and specify the fuzzy solution you desire.
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Will "Fuzzy" solutions give away my cache location?
If you specify an exact solution, absolutely not. All the solver will get is a yes/no answer, and only "yes" if they get it exactly correct. If you specify a fuzzy solution, we still don't give away anything - we only inform the solver if they're within the specified distance. The Google maps link and coordinates will only reflect the solver's OWN solution (not your official answer), EVEN IF it's not exactly correct.
However, it's worth noting that offering a fuzzy solution would make it easier to "brute force" solve a cache - trying a solution every hundred feet is a lot less difficult than trying one every six feet. So only use the fuzzy solution if you have a good reason, and only use the 100 foot solution if you really really have a good reason. Of course, knowing you're within 100 feet can still make for an awful large area to search.
If you lose these special links (PLEASE don't!), you will need to recreate the solution, using the exact same info (cache name, waypoint, and coordinates); you will get the same links again. We recommend that you save a copy of the web page with those links: Select File:Save As from your browser menu and keep it on your PC with your other puzzle information.
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I'm a cache owner, and I need to recreate my link. But I don't want to lose the stats you collect.
If you keep the same waypoint name (GCXXXX) and coordinates when you create a link, the number of solution attempts will keep updating as before. However, the special detailed information is tied to the cache coordinates (for security) and so if you change the coordinates, the stats will restart.
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Hey. Nothing works quite right. What have you done?!