Tank Capacity Calculator
Volume of a vertical cylindrical tank from diameter and height.
Calculator
No signup required. Results are indicative—verify for your standards.
Capacity: 28.274 m³ · 28274 L
Formula
Vertical cylinder: V = π × r² × h = π × (D/2)² × h, with D diameter and h straight-shell height (exclude dished ends for rough estimate or add separately).
Example calculation
Tank diameter 3 m, liquid height 4 m: V = π × 1.5² × 4 ≈ 28.27 m³.
Engineering notes
Add head volumes separately for horizontal tanks or dished ends. Check max fill level vs overflow and instrumentation.
When to use this calculator
- Water storage sizing — determine tank diameter and height for a required volume at a plant or site
- Chemical storage planning — size storage tanks for acids, solvents, or process chemicals
- Fire water tank design — verify that a proposed tank meets the required firefighting water reserve
- ETP/STP design — calculate retention volume for effluent treatment or sewage treatment pits
- Project cost estimation — estimate tank shell area for material take-off and cost budgeting
Frequently asked questions
- Does this calculator include the volume of dished or conical heads?
- No. This calculator computes only the cylindrical shell volume using the straight-shell height. For ASME standard 2:1 elliptical heads, add approximately 0.131 × D³ per head (where D is the inner diameter in metres). For flat heads, no additional volume. For cone bottoms, add the cone volume separately: V_cone = (π/3) × r² × h_cone.
- How do I find the working (usable) volume of a tank?
- The working volume is between the high-level alarm (HLA) and the low-level alarm (LLA). Subtract the dead volume (below LLA) and the vapor space (above HLA) from the total geometric volume. Typically the dead volume is 5–10% of total capacity and the vapor space is 10–15%, leaving around 75–85% usable working volume.
- What tank diameter gives the most cost-effective storage?
- For a given volume, a cylinder with height equal to diameter (H = D) minimises the surface area and therefore material cost. However, site constraints, foundation loading, and wind loading often dictate a taller, narrower tank to reduce footprint. As a starting point, design for H/D ratios between 0.8 and 1.5.
- How do I calculate the capacity of a horizontal cylindrical tank?
- For a fully filled horizontal cylinder, the formula is the same: V = π × r² × L, where L is the length (horizontal axis). For a partially filled horizontal cylinder, the cross-sectional area depends on the fill depth and requires a segment area formula. This calculator covers vertical cylinders; for horizontal tanks, use the same formula at 100% fill level.