Free fish tank volume calculator. Enter dimensions to get water volume in liters and gallons, total weight, and net volume adjusted for glass thickness.
Tank volume determines how many fish you can keep, how much filtration you need, and how often you need water changes. Accurate volume calculation is essential for maintaining a healthy aquarium. Larger tanks are more stable and easier to maintain.
Measure the inside dimensions of your tank in inches or centimeters. For rectangular tanks, measure length × width × height. For cylindrical tanks, measure diameter and height. For irregular shapes, fill with water and measure the volume directly.
Tank volume is the total capacity, while water volume is less due to substrate, decorations, and equipment. Typically, actual water volume is 80-90% of tank volume. Use water volume for stocking calculations.
This calculator is based on geometric formulas for standard tank shapes. Actual volume may vary slightly due to tank thickness and decorations. For precise measurements, fill your tank and measure.
1 gallon = 3.785 liters. To convert gallons to liters, multiply by 3.785. To convert liters to gallons, divide by 3.785. The calculator handles this conversion automatically.