pH Calculator
How to Use?
- 1
Choose what you know
Select whether you have [H⁺] concentration, [OH⁻] concentration, or pOH value.
- 2
Enter the numeric value
For concentrations, you can also enter the exponent (e.g., 1.0 × 10⁻⁵ becomes 1.0 and -5).
- 3
View your results
The calculator instantly displays the pH, pOH, and the solution type (acidic, neutral, or basic).
Worked Examples
Calculate pH from [H⁺] = 1.0 × 10⁻³ M
Given:inputs
Calculate from:[H⁺] concentration (mol/L)
[H⁺] concentration:1.0
× 10 ^:-3
Result:calculated
pH:3.0000
pOH:11.0000
Solution Type:Acidic
Calculate pH from [OH⁻] = 2.5 × 10⁻⁵ M
Given:inputs
Calculate from:[OH⁻] concentration (mol/L)
[OH⁻] concentration:2.5
× 10 ^:-5
Result:calculated
pH:9.3979
pOH:4.6021
Solution Type:Basic / Alkaline
Calculate pH from pOH = 5.5
Given:inputs
Calculate from:pOH value
pOH value:5.5
Result:calculated
pH:8.5000
pOH:5.5000
Solution Type:Basic / Alkaline
FAQs
1.What does pH stand for?
+pH stands for "potential of hydrogen." It measures the concentration of hydrogen ions in a solution. Lower pH means higher acidity, higher pH means higher alkalinity.
2.Can I use this calculator for non‑aqueous solutions?
+The calculator assumes water‑based solutions at 25°C, where the ion product constant (Kw) equals 1×10⁻¹⁴. For other solvents or temperatures, results may differ.
3.Why do I need to enter both a value and an exponent?
+Many concentrations in chemistry are expressed in scientific notation (e.g., 1.0×10⁻⁵ M). Splitting the input lets you enter the coefficient and exponent separately for accuracy, but you can also enter the full number (like 0.00001) directly in the first field and leave the exponent blank.
4.What does the status indicator mean?
+The calculator flags results: "warning" for acidic (pH<7), "ok" for neutral or basic. This is a visual helper for quick interpretation.