Boat fender placement plan calculator

Calculate fender count and equally spaced positions from protected-length start with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use fender count and equally spaced positions from protected-length start to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Protected hull length (m)
8
Maximum chosen fender spacing (m)
2
Unprotected end margin each end (m)
0.5
Fender count
5
Equally spaced positions from protected-length start (m)
[0.5,2.25,4,5.75,7.5]
Actual spacing (m)
1.75

Try another scenario

Protected hull length (m)
8.8
Maximum chosen fender spacing (m)
2
Unprotected end margin each end (m)
0.5
Fender count
5
Equally spaced positions from protected-length start (m)
[0.5,2.45,4.4,6.35,8.3]
Actual spacing (m)
1.95
Calculation method

Calculation method

Fender count

Protect [margin,L-margin]; n=max(2,ceil(span/maxSpacing)+1), include both endpoints.

Equally spaced positions from protected-length start (m)

Protect [margin,L-margin]; n=max(2,ceil(span/maxSpacing)+1), include both endpoints.

Actual spacing (m)

Protect [margin,L-margin]; n=max(2,ceil(span/maxSpacing)+1), include both endpoints.

Symbols and units
a
Protected hull length (m)
b
Maximum chosen fender spacing (m)
c
Unprotected end margin each end (m)

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • User-selected geometric positions, no impact/load or berth-protection certification. Supported limits: All required fields must be finite values of the exact declared type and within displayed bounds. Lists contain1–1000 finite numbers. JSON tables are numeric rectangular rows, at most100 rows and30 columns; individual tools have stricter shape/domain constraints. User-selected geometric positions, no impact/load or berth-protection certification.
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