$12.00 for 1 year



Membership grants access to the Multihull Dynamics website for 1 year. *

  • Access to database of over 1100 multihulls, compare up to 5 vessels at a time using our 12 point design analysis. You may print your comparisons and custom evaluations through your browser.
  • Advanced Search Engine – search for vessels in our database by using either 1 specification or using up to 8 different specifications: Loa, Lwl, SA, Boa, Displacement, Bruce Number, Base Speed and/or Stability Speed
  • The DIY Custom Evaluation tool – allows to you to configure a vessel and calculate its performance and stability. You can use it to calculate how increasing/reducing sail area or increasing/reducing weight will affect a boat’s performance and stability. The Custom Evaluation also helps multihull sailboat builders better understand designs they may wish to build or modify.
  • Cal’s Evals, Technical articles on design and more
  • Multihull Forum available only to Members
  • A free download of  Analysis and Comparison of Cruising Multihull, 2013  by Calvin H. Markwood, Engineering Analyst –  an excellent Primer on multihull sailboat analysis and explains why Multihull Dynamics, LLC goes about the analysis of multihull sailboats in the manner that we do.


*Follow this link for details about our 12 point multihull design analysis; when all data is available.  Look at the Sample Comparison to understand what type of data you are purchasing and how it will be displayed.   The 12 point analysis is displayed in two ways: Bar Graph or Table display, tabs are at the top of page for display choice.

Read our statement on Database Accuracy.

Bridgedeck Clearance height continues to be the most difficult information to collect.  Consequently Bridgedeck Clearance (BdCl) and Nominal (Nom) comparison may not be available;  if data is Not Available it is displayed as N/A.  That said, when Bridgedeck Clearance measurements are known, Cal Markwood’s Nominal Bridgedeck Formulas are very helpful when deciding between two or more multihulls.


There is no refund.