Draft Calculator
Summarize observed forward and aft drafts as a simple arithmetic mean and signed draft difference.
Inputs
Updates as you typeResults
Mean draft
| Forward draft | 7.8 m |
|---|---|
| Aft draft | 8.5 m |
| Trim · AFT − FWD | 0.7 m |
| Trim condition | Trim by Stern |
Overview
Summarize observed forward and aft drafts as a simple arithmetic mean and signed draft difference.
Formula
Mean draft = (FWD + AFT)/2 Difference = AFT − FWD
Example
How to use
- Check the units, enter the required values and select the available calculation options.
- Results update immediately. Correct any highlighted input before using the result.
- Choose display precision, copy the result or share the current inputs. Reset restores the example values.
Engineering notes
- This is a two-point geometric calculation. Draft-mark position, port/starboard readings and hull deformation corrections are excluded.
- It does not calculate displacement, stability or loading approval. Use the vessel's approved data and correction procedures.
Frequently asked questions FAQ
Can I calculate draft from displacement?
No. That requires vessel-specific hydrostatic data and water density. This calculator only summarizes draft readings you enter.
Does display precision change the calculation?
No. Rounding is applied only to displayed results, not intermediate calculations. Small nonzero values use scientific notation. Consider the precision of the original measurements when interpreting results.
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