Navigation Sight Reduction Calculators

The following links are interactive calculators for reducing sights. Once you have clicked on the link, you can do "save as" in your browser to save the page. This allows you to use the calculators while you are disconnected from the web by accessing the saved page with your browser. This works because these pages are written in JavaScript which runs locally in your own browser and does not depend on a server.

Navigation Manual Sight Reductions Using The ABHAV method

Here is a paper on a simplified Sight Reduction Method and an online sight reduction calculator that can be used to check answers.


Disclaimer: Always use multiple methods to check your results when navigating. While these tables and formula are believed to be correct, every entry has not been checked against a second computational method.

Comments can be mailed to the Webmaster at: webmaster@snark.dhs.org


This is a javascript test link called jstest. It will likely give meaningless or wrong output. Don't use.
This is a javascript test link called jstest1. It may give meaningless or wrong output, but is the latest and greatest.