you can always use navionics website.... There chart viewer is a great way of planning routes and distances. Just did an aoutomatic routing from Nanny Cay to Leverick with a way point at the tip of the Cualquhuan reef. 18.1nms



https://webapp.navionics.com/?lang=en#boating/routing/automatic@11&key=_%60%7DoBje%7DgK