Tank & Vessel Volume Calculator

Exact partial-fill volume · Vertical & horizontal · Flat / ellipsoidal / hemispherical / ASME torispherical heads · Free

Get tank volume in seconds

Enter diameter, length, head type and liquid level — get exact liquid volume, total capacity and % full in litres or gallons.

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What this calculator does

Whether you're doing an inventory dip, sizing a surge drum, or checking a truck load, you need the liquid volume at a given level — not just the full capacity. EnggiBasis computes the exact partial-fill volume for vertical or horizontal vessels with realistic dished heads, and reports total capacity, liquid volume, ullage (empty space) and percent full.

The geometry

1. Cylindrical shell

Vertical: V = π·R²·h. Horizontal (filled to depth h): the wetted cross-section is a circular segment,

A = R²·acos((R−h)/R) − (R−h)·√(2Rh − h²), and V = A·L.

2. Heads (dished ends)

Head volumes are found by integrating the exact head profile. Common full-head volumes:

Head typeFull volume
Hemispherical(2/3)·π·R³
2:1 Ellipsoidalπ·D³/24 ≈ 0.1309·D³
ASME F&D torispherical≈ 0.0809·D³
Flat0

EnggiBasis integrates the true meridian profile (including the crown-sphere + knuckle-torus of an ASME torispherical head), so partial-fill volumes in the heads are exact too — for both orientations.

Worked example

InputValue
OrientationVertical
Inside diameter2000 mm
Straight length4000 mm
Heads2:1 ellipsoidal
Liquid height3000 mm

Result: total capacity 14,661 L, liquid volume 8,901 L, 60.7% full. Try it with your own tank →

FAQ

How do you calculate the volume of a partially filled tank?

Add the cylindrical-shell volume (circular-segment area × length for horizontal) to the head volumes at the given level. EnggiBasis does both exactly.

What is the volume of a 2:1 ellipsoidal head?

Full volume = πD³/24 ≈ 0.1309·D³.

Is it free?

Yes — completely free.

Calculate your tank volume

Free · Vertical & horizontal · All head types

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