The Nautical Almanac
The free online Nautical Almanac
The world's most complete source of free celestial navigation information

The Nautical Almanac
1911, 1916, 1981 & 1999 through 2025

Everything you need
for 2018

click here

The Sun only Almanac
2015 through 2025

Astronomical Phenomena
2015 through 2018

Essential Celestial Navigation downloads

Increments & Corrections, Altitude Corrections & Polaris Q Corrections

Sight Reduction Tables

  • PUB. NO. 249  (download individual Latitudes or Volumes) (courtesy of Celestaire) (also known as Ho- 249)
  • PUB. NO. 229  (download individual volumes) (also known as Ho- 229)

    Complete Sun & Star sight reduction Procedure

‣  Methods & Forms

‣  Formulas for Celestial Navigation

‣  Artificial Horizon

‣  Useful Links

‣  Sun Sight Reduction Excel Spreadsheet
            A Sun sight reduction program!  From

Complete Celestial Sight Reduction Excel Spreadsheet
            Covers all navigational bodies. 

Complete Celestial Sight Reduction Spreadsheet in ODS format
            Covers all navigational bodies.  Can be used in LibreOffice Calc.

Celestial Navigation Forum
            Discuss and learn about Celestial Navigation- All are welcome

The Terrestrial Almanac- 2018 through 2020
            Calendars for the World and United States
              Agreeable to the Northern and Southern Hemispheres
            Also has Day of Year number chart


The American Practical Navigator

Organized in a useful manner
Download the Chapters you want or the entire work

The Nautical Almanacs and Sun Almanacs listed at the top of our site were created or derived from a program written by the great Norwegian sailor Enno Rodegerdts.  Without his work this site wouldn't exist.

Disclaimer and Warning
Prior to use verify the accuracy of The Nautical Almanac or data you download from this site.  They SHOULD NOT and MUST NOT be relied upon for celestial navigation work of any sorts or any purpose whatsoever.  You use them at your own risk or peril.

Copyright 2017

All material on this website, except Pub. 229 & Pub. 249, or where copyright is imprinted, is the property of  You are free to copy and distribute, but not sell, any material on these webpages provided attribution to the is included.

...freely ye received, freely give...

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fair winds, clear skies & following seas