Lashing Design App (IMO CSS) – with Stoppers




Spreadsheet for Lashing calculation as per IMO CSS – with Stoppers


This Excel app helps you to calculate the external forces acting on a cargo unit in longitudinal, transverse and vertical directions during sea transportation.
Furthermore, the app is calculating the restrain provided by soft and/or hard lashing in different direction and assist you in calculating the required min lashing in order to secure the cargo for sea passage.

How to use?

The user is asked to provide input such as Ship’s particulars, cargo weight, stowage position, COG, information for the lashing etc.
The Input cells are highlighted in blue or yellow.
Additional information and guidelines for the different input required can be found in the guide sheet.


The acceleration figures shown in table 3 and table 4 in annex 13 are basis for the calculation of accelerations and apply in principle to ships with 50 m £ L £ 200 m, 9 kn £ V £ 24 kn and B/GM ≥ 7 ( CSS Code Annex 13 2011) or B/GM ≥ 3 (CSS Code Annex 13 2020). The formula for length/speed correction factor shall not be used for ships lengths less than 50m or more than 300m

The yield tension for any calculation applies to mild steel of strenght class S235 for material thickness of up to 20 mm and is taken for the safety class “Normal” as 18,0 kN/cm². The appropriate permissible shear stress is 10,4 kN/cm²

The stoppers calculations are for fillet seam “ordinary quality” with permissible stressed pull/bending 10,0 kN/cm², pressure 10,6 kN/cm² and shear 8,7 kN/cm².


1. IMO Code of safe practice for cargo stowage and securing 2011 Edition
2. MSC.1/Circ. 1623 Amendments to the code of safe practice for Cargo Stowage and Securing (CSS Code) 2020
3. BBC Chartering BBC Guideline Safe Solutions for Project Cargo Operations Version 1.0

For feedbacks, write to

Additional information

License Type


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.

Please visit our FAQ page for all questions on usage of our products. For any issues, please write to

FAQs on Products

Important: Our excel-based products work only on Windows machines, and not on Macs

System Requirements:

MS Excel 2013 and up

Windows 7 and up