Water Potential Calculator
💧 Diffusion, osmosis & transport. Use the Water potential formula to find water potential ψ, solute potential ψs, pressure potential ψp: pick the value you want, type the others, and the answer updates as you go.
Water moves from a higher (less negative) to a lower water potential.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Water potential Ψ | kPa |
| Solute potential Ψs | kPa |
| Pressure potential Ψp | kPa |
Worked example
Find the water potential ψ when Solute potential Ψs = -700 kPa, Pressure potential Ψp = 300 kPa.
Using = +: Water potential Ψ = -400 kPa.
Frequently asked questions
What is the formula for Water potential?
= +. Water moves from a higher (less negative) to a lower water potential.
What do the letters stand for, and what units are used?
Water potential Ψ in kPa, Solute potential Ψs in kPa, Pressure potential Ψp in kPa.
How do you calculate water potential ψ?
Put the values into = +. For example, with Solute potential Ψs = -700 kPa, Pressure potential Ψp = 300 kPa, water potential ψ = -400 kPa.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (water potential ψ, solute potential ψs, pressure potential ψp) and fill in the others: it rearranges the formula for you.
