pH to pOH Calculator
To convert either a pH value or a pOH with pH to pOH calculator enter values between 0 and 14. Do not enter both values simultaneously. For example, enter 7.0 for neutral solutions in the pH field, or 7.0 in the pOH field.
The calculator will compute the pOH using the formula pOH = 14 − pH.
pH to pOH Calculator
| pH Value | pOH Value | Conversion Formula |
|---|---|---|
| pH = 0 | pOH = 14 – pH | pOH = 14 – 0 = 14 |
| pH = 1 | pOH = 14 – pH | pOH = 14 – 1 = 13 |
| pH = 2 | pOH = 14 – pH | pOH = 14 – 2 = 12 |
| pH = 3 | pOH = 14 – pH | pOH = 14 – 3 = 11 |
| pH = 4 | pOH = 14 – pH | pOH = 14 – 4 = 10 |
| pH = 5 | pOH = 14 – pH | pOH = 14 – 5 = 9 |
| pH = 6 | pOH = 14 – pH | pOH = 14 – 6 = 8 |
| pH = 7 | pOH = 14 – pH | pOH = 14 – 7 = 7 |
| pH = 8 | pOH = 14 – pH | pOH = 14 – 8 = 6 |
| pH = 9 | pOH = 14 – pH | pOH = 14 – 9 = 5 |
| pH = 10 | pOH = 14 – pH | pOH = 14 – 10 = 4 |
| pH = 11 | pOH = 14 – pH | pOH = 14 – 11 = 3 |
| pH = 12 | pOH = 14 – pH | pOH = 14 – 12 = 2 |
| pH = 13 | pOH = 14 – pH | pOH = 14 – 13 = 1 |
| pH = 14 | pOH = 14 – pH | pOH = 14 – 14 = 0 |
| pH = 15 | pOH = 14 – pH | pOH = 14 – 15 = -1 |
| pH = 16 | pOH = 14 – pH | pOH = 14 – 16 = -2 |
| pH = 17 | pOH = 14 – pH | pOH = 14 – 17 = -3 |
| pH = 18 | pOH = 14 – pH | pOH = 14 – 18 = -4 |
| pH = 19 | pOH = 14 – pH | pOH = 14 – 19 = -5 |
| pH = 20 | pOH = 14 – pH | pOH = 14 – 20 = -6 |
pH to pOH Conversion Formula
pH + pOH = 14- [H⁺] = 10^(-pH) mol/L
- [OH⁻] = 10^(-pOH) mol/L
- pH = -log[H⁺]
- pOH = -log[OH⁻]
Parameters
- pH: Negative logarithm of hydrogen ion concentration (0-14)
- pOH: Negative logarithm of hydroxide ion concentration (0-14)
- [H⁺]: Hydrogen ion concentration in mol/L
- [OH⁻]: Hydroxide ion concentration in mol/L
For a solution with pH = 3:
- pOH = 14 – 3 = 11
- [H⁺] = 10^(-3) = 1.00 × 10^-3 mol/L
- [OH⁻] = 10^(-11) = 1.00 × 10^-11 mol/L
How to Convert pH to pOH?
- Start with the fundamental relationship: pH + pOH = 14
- To find pOH from pH: pOH = 14 – pH
- To find pH from pOH: pH = 14 – pOH
- You can verify the calculation using [H⁺][OH⁻] = 10^-14
If pH = 5, then:
- pOH = 14 – 5 = 9
- [H⁺] = 10^-5 mol/L
- [OH⁻] = 10^-9 mol/L
What is pH and pOH?
pH is a measure of the hydrogen ion concentration [H⁺] in a solution. It is defined as the negative logarithm (base 10) of the hydrogen ion concentration. The pH scale ranges from 0 to 14, where 7 is neutral, below 7 is acidic, and above 7 is basic.
pOH is a measure of the hydroxide ion concentration [OH⁻] in a solution. It is defined as the negative logarithm (base 10) of the hydroxide ion concentration. Like pH, the pOH scale ranges from 0 to 14. A high pOH indicates low hydroxide concentration (acidic), while a low pOH indicates high hydroxide concentration (basic).