pH Calculator
Convert between hydrogen ion concentration, pH and pOH.
Inputs
Formula
- pH = −log₁₀[H⁺]
- pOH = 14 − pH
pH is the negative base-10 logarithm of the hydrogen ion concentration at 25 °C.
Step-by-step calculation
- 1
pH
−log₁₀(0.0001)
4
Frequently asked questions
What does the pH Calculator do?
Convert between hydrogen ion concentration, pH and pOH. The pH Calculator on OneCalcApp returns the result instantly as you type, together with the formula and the substituted values.
How do I use the pH Calculator?
Enter your values in the input fields, choose the relevant units or options, and the pH Calculator recalculates automatically. You can copy, print or export the result.
Is the pH Calculator free to use?
Yes. The pH Calculator is completely free, needs no sign-up and has no usage limit on OneCalcApp.
How accurate is the pH Calculator?
It uses the standard formula pH = −log₁₀[H⁺] and full double-precision arithmetic, so results match a manual calculation to the displayed number of digits.
Does the pH Calculator work on mobile and offline?
Yes. The pH Calculator runs entirely in your browser on phones, tablets and desktops, and your inputs never leave your device.
Where can I find related tools?
OneCalcApp hosts 300+ calculators and converters, including the full Math collection. Related tools are linked at the bottom of every page.
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