Welcome to Geochecker, a simple tool to check coordinates for geocaching puzzle caches. It's completely free, and it's very easy to use!
Since you either requested help, or visited this site without coordinates to check, you can read some simple instructions below, or watch this handy how-to demonstration video. You can also learn more about GeoChecker in the frequently asked questions.
If you'd like to try it, here is a sample geocache link for an imaginary cache. The coordinates are encoded for N38 00.000, W76 00.000.
You can learn more about these topics by clicking the [ + ] link next to each question to expand its answer. Or expand all the topics at once.
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Usage for Cache Owner
If you are a puzzle cache owner, and you would like to use this site to let solvers check their solutions, it's very easy. Simply enter the cache name, waypoint, and GPS coordinates to be checked in the boxes below and submit the data. The next page will present you with the HTML code for a hyperlink to be inserted into the cache description. It's important to use the complete link for the checker to work properly. It's also a good idea to make sure that the link works properly and that the correct coordinates return a positive result. (This tool assumes coordinates are in the typical WGS84 datum used by Geocaching.com.) As the cache owner, you will be able to track how many solutions are attempted - both good and bad. This is a great way to make sure your puzzle is not proving too easy or too hard.
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Usage for Puzzle Solver
On various puzzle caches, you will find a link to this site, with some encoded information. You simply follow the link to this site and enter the coordinates and submit the form. You will then be told if the coordinates entered match the code in the link.
If you don't find a link to this site on your puzzle nemesis, contact the cache owner and suggest this site. But don't bother with the form below - you'll just end up checking your own solutions! Naturally your own answers would agree with themselves... that really won't help, will it?
Once you have a correct solution, we even make it easier by providing a Google Maps overview of the cache location. How much easier can it get?
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When you check cache coordinates, you will need to enter a five-digit numeric code. This helps to prevent automated solution attempts. Also, you are limited to 10 attempts in any 10 minute span - this should be enough to try a few solutions without interruption, but should prevent attempts to attack cache coordinates via scripting. For this reason, your IP address and what actions you take are logged, but coordinates are NOT logged
. Log files are periodically recycled and are not permanently stored. You can read more about GeoChecker's security in the frequently asked questions.
Please note that because coordinates are not logged, and because of the one-way hash, it is IMPOSSIBLE to recover coordinates from this tool. Please do not ask - it simply cannot be done. If you lose the encoded link, simply create it again!
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This is a free tool. You are guaranteed to get what you have paid for. In other words, there are no guarantees! This tool should work as advertised, but if it does not, please don't blame us. With that said, we welcome your feedback.
FREQUENTLY ASKED QUESTIONS
Welcome to Geochecker, a simple tool to check coordinates for geocaching puzzle caches.
You can learn more about these topics by clicking the [ + ] link next to each question to expand its answer. Or
expand all the topics at once.
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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.
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What about statistics? What do you log?
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.
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What about security? Is this tool safe?
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!
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I am having trouble with the Security Code.
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
would match, and and any West solution from 76 20.190
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.
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Help! I lost my special cache owner links!
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?!