When selecting food processing equipment like kettles, tanks, or mixers, understanding how to calculate capacity and volume is essential. These measurements help determine whether a piece of equipment can handle your production needs — whether you're processing sauces, soups, dry goods, or blended ingredients. Regal Equipment provides detailed specs for each piece of equipment, but knowing how to interpret or calculate those numbers ensures you're investing in the right fit for your operation. 

Is Capacity the Same as Volume? 

Not quite — though they’re often used interchangeably, capacity refers to how much a container can hold, while volume is the actual space inside the container. In other words, volume is a measurement of three-dimensional space, and capacity is how much material — like liquid, powder, or solid — that space can contain. When browsing Regal Equipment’s inventory, volume tells you the internal size of the tank or kettle, and capacity helps you determine if it meets your batch size or throughput requirements. 

How to Measure Volume: Common Container Shapes 

To calculate how to measure volume for containers like tanks, kettles, or blenders, start with the shape and basic dimensions. Here are the most common shapes and formulas: 

• Rectangle or Cube: 
• Volume = Length × Width × Height 
• Example: A rectangular blender that’s 60" long, 36" wide, and 48" high: 
• 60 × 36 × 48 = 103,680 cubic inches 
• Cylinder (common for tanks): 
• Volume = π × Radius² × Height 
• Example: A cylindrical tank with a 36" diameter (18" radius) and 60" height: 
• 3.1416 × 18² × 60 = 61,236 cubic inches 
• Sphere (less common, but used in some mixing vessels): 
• Volume = (4/3) × π × Radius³ 
• Example: A spherical chamber with a 30" diameter (15" radius): 
• (4/3) × 3.1416 × 15³ = 14,137 cubic inches 
• Cone (used in hoppers or funnel-bottom tanks): 
• Volume = (1/3) × π × Radius² × Height 
• Example: A cone-shaped hopper with a 24" diameter (12" radius) and 36" height: 
• (1/3) × 3.1416 × 12² × 36 = 5,429 cubic inches 

These formulas provide volume in cubic inches, which can then be converted to gallons or liters for practical use when comparing Regal’s equipment specs. 

Round Water Tank Capacity Formula 

To calculate the capacity of a round water tank, you’ll use the volume formula for a cylinder: 

Volume = π × Radius² × Height 

For example, a tank with a 48" diameter (24" radius) and a 72" height would be: 

3.1416 × 24² × 72 = 130,288 cubic inches 

To convert that into usable capacity: 

130,288 ÷ 231 = ~564 gallons 

How to Calculate Capacity in Gallons or Liters 

Once you've measured the volume of a container in cubic inches, converting it to capacity is straightforward: 

• To Gallons: 
• Cubic Inches ÷ 231 = US Gallons 
• To Liters: 
• Cubic Inches ÷ 61.0237 = Liters 

For example, a volume of 207,360 cubic inches equals: 

• ~897.2 gallons 
• ~3,398 liters 

Helpful Conversions for Food Equipment Sizing 

Quick reference conversions make it easier to interpret volume and capacity when sizing Regal’s equipment: 

• 1 US Gallon = 231 cubic inches 
• 1 Liter = 61.0237 cubic inches 
• 1 US Gallon = 3.785 liters 
• 1 US Gallon of water = 8.35 lbs 
• 1 Cubic Foot = 7.5 gallons 
• 1 Cubic Foot = 1,728 cubic inches 

Apply These Formulas to Your Equipment Search 

Whether you’re evaluating a stainless steel tank or an industrial kettle, these volume and capacity formulas can help you make informed decisions. Use them alongside the detailed specifications listed on Regal Equipment’s product pages to ensure the equipment you choose aligns with your production goals. Not sure where to start? Browse our tanks and kettles to compare capacities and find the right fit.