pH Calculator

A pH calculator for strong acids and strong bases. Enter a concentration to get the pH, the pOH and both ion concentrations, enter a pH to get the concentrations back, or dilute a solution and see where the pH lands. It solves the full charge balance rather than using pH = -log10(C), so a very dilute acid approaches 7 from below and never crosses it, and the page says when the shortcut would have been wrong. Weak acids are not covered, because each one needs its own dissociation constant.

Calculator Type

Give the concentration of a strong acid or a strong base and get the pH, the pOH and both ion concentrations.

The amount you made up, not the ion concentration. Scientific notation such as 1e-8 is accepted.
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Work the other way: a measured pH back to the ion concentrations.

Values below 0 and above 14 are real and are allowed.
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Both Volumes Are In
One choice for both boxes, because a dilution is the ratio between two volumes measured the same way. The dilution factor and the pH do not depend on it; the amount of solvent to add is reported in whichever you pick.

Dilute a strong acid or base and see what the pH does. Uses C1 x V1 = C2 x V2, then the exact pH of the result.

Scientific notation such as 1e-6 is accepted.
In the unit selected above.
In the unit selected above. This is the total volume when you are done, not the solvent you add.
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Related Tools
Chemical Equation Balancer Molarity Calculator Dilution Calculator