Web sites that offer assistance on how to solve geocaching puzzles.
BOXENTRIQ
Cache the Line Puzzle Tools
Certitude
Cipher Tools
dCode
GC Wizard
(puzzle solving app for Android)
GC Wizard
(puzzle solving app for IOS)
GC Wizard
(puzzle solving for home computers)
Geocaching Mysteries Revealed
Geocaching Puzzle Help
Geocaching Puzzle of the Day
Geocache Puzzle Spoilers Spreadsheet
Georgia Geocaching Puzzle Society
How to Puzzle Cache
How to Puzzle Cache, 2nd Edition
Jigidi, Online Puzzle Creator
MultiSolver
Pi Search Page
Puzzle Cache Practice
Puzzlehead
Geocaching Central