About The Tank Fill Drain Time Calculator

The Tank Fill Drain Time Calculator estimates net flow rate and time required for a tank to fill or drain from tank volume, inflow, and outflow.

How to Use the Tank Fill Drain Time Calculator Online

1. Enter tank volume in cubic meters.
2. Enter inflow and outflow rates in cubic meters per hour.
3. Run the calculation to see net flow and estimated time in hours and minutes.
4. Confirm whether the tank is filling or draining based on the net flow sign.

Choosing Options Correctly

Flow rates:
Use average rates for planning. Variable pump curves, valve positions, or changing head require a more detailed model.

Zero net flow:
If inflow equals outflow, tank level will not change and the tool reports an error.

Common Use Cases

• Estimate fill time for storage tanks or process vessels.
• Estimate drain-down time under a known outlet rate.
• Check how simultaneous inflow and outflow affect level change.

Quick FAQ

What does this estimate?
It estimates the time to fill or drain a tank from flow rate or outlet assumptions.

Does draining always use constant flow?
No. Gravity drain flow changes as head changes unless the tool assumes constant flow.

What tank volume should I use?
Use usable volume between the starting and ending levels, not necessarily total tank capacity.

Can this size emergency drainage?
No. Critical drainage needs code, safety, overflow, and hydraulic checks.