Convert pot dimensions into usable volume in seconds. Compare liters, quarts, and gallons for planning. Get soil estimates that reduce waste and improve growth.
Choose a pot shape. Enter dimensions and press calculate. Large screens show three columns, smaller screens adjust automatically.
| Shape | Inputs | Computed Volume | Recommended Soil |
|---|---|---|---|
| Tapered | Top 32 cm, Bottom 24 cm, Height 28 cm | ≈ 18.03 L | Fill 95%, Overfill 5% → ≈ 17.97 L |
| Cylinder | Diameter 30 cm, Height 25 cm | ≈ 17.67 L | Fill 90%, Overfill 5% → ≈ 16.69 L |
| Rectangular | Length 40 cm, Width 25 cm, Height 20 cm | 20.00 L | Fill 92%, Overfill 3% → ≈ 18.98 L |
Retail labels like “10 inch pot” describe rim diameter, not capacity. Two pots with the same top diameter can hold very different amounts of mix because height and taper change the interior space. Converting diameter and height into liters gives a consistent planning unit for watering, fertilizing, and media purchasing across brands and shapes. Standardizing to liters helps compare nursery pots, decorative planters, and grow bags on equal footing.
Container volume influences how fast moisture is depleted. Smaller volumes dry quickly and need shorter irrigation intervals, while larger volumes buffer heat and wind stress. When you know liters, you can estimate daily water demand, choose drip emitter flow rates, and set safer runtimes that avoid both drought stress and chronic saturation.
Potting mixes are sold by volume, so liters convert directly into bags, bales, and mixing recipes. Use fill level to reserve headspace for watering and mulching, then add overfill to cover settling after the first few irrigations. This improves batching consistency when blending compost, perlite, coco coir, or controlled release fertilizer. For large projects, volume totals support delivery planning, storage space, and cost control across beds.
Usable volume is usually lower than the geometric volume. Thick walls, internal ribs, and a raised drainage base reduce space for roots and media. Measuring internal dimensions improves accuracy. The calculator’s soil recommendation helps you avoid underfilling, which limits rooting, and overfilling, which reduces headspace and causes runoff during watering.
Repotting is easier when you compare old and new container volumes rather than guessing by diameter alone. Many growers target a 20–50% increase in volume to encourage fresh root growth without leaving excess wet media. By checking liters before transplanting, you can pick the next size logically and maintain stable irrigation routines. Tracking volume changes over seasons supports yield records, nutrient adjustments, and container spacing in nurseries.
Answer: Choose the option that matches the interior walls. Most nursery pots are tapered. If the sides look straight, use cylinder. For window boxes or troughs, use rectangular planter.
Answer: Measure internal dimensions whenever possible. Wall thickness and drainage bases reduce usable space. If you only have outside measurements, expect the real volume to be slightly lower than the estimate.
Answer: Select inches as the unit and enter measurements in inches. The calculator converts to centimeters internally, then reports liters, quarts, and gallons using standard volume conversions.
Answer: Common practice is 90–95% to keep headspace for watering and mulch. Use a lower value for plants that need heavier top watering or for pots that receive frequent rainfall.
Answer: Fresh mixes settle after watering and handling. Adding 3–10% overfill helps ensure you have enough media for top-ups and reduces the chance of underfilled containers exposing roots.
Answer: Yes. Treat a grow bag as a cylinder using the bag’s opening diameter and filled height. Because bags bulge, the estimate is approximate, but it is still useful for ordering soil.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.