pH Calculator: From Concentration to Acidity
pH compresses a huge range of concentrations into a small scale. A negative logarithm does that compression, and this calculator shows the working.
What is the pH Calculator?
Enter the hydrogen ion concentration in mol/L. The tool takes the negative base-10 logarithm for pH, finds pOH from 14 minus pH, and labels the solution acidic, neutral, or basic. It assumes water at about 25 C, where pH plus pOH equals 14.
How to use it
- Enter hydrogen ion concentration in mol/L.
- Click Calculate pH.
- Read pH, pOH, and the classification.
Worked example
A hydrogen ion concentration of 0.001 mol/L gives pH 3 and pOH 11, classified acidic.
What is the pH of 0.001 mol/L hydrogen ions?
pH 3, with pOH 11, which is acidic.
Frequently asked questions
Why is pH logarithmic?
Concentrations span many orders of magnitude, so a log scale keeps them readable.
Does temperature matter?
Yes. pH plus pOH equals 14 only near 25 C in water.