pH & Chemistry Calculator

Convert between pH, pOH, Hydrogen [H+], and Hydroxide [OH−] concentrations instantly.

[H+] = × 10 M
Current pH 7.00
Neutral
pOH Value 7.00
[OH−] Concentration 1.00 × 10-7 M

Chemistry Formulas

The pH scale measures how acidic or basic a water-based solution is. It is a logarithmic scale, meaning each whole number change represents a 10-fold change in acidity.

  • pH Formula: $pH = -\log_{10}[H^+]$
  • pOH Formula: $pOH = -\log_{10}[OH^-]$
  • The Constant: At 25°C, $pH + pOH = 14$

The Scale: A pH of 7 is perfectly neutral (like pure water). Values below 7 are acidic (like lemon juice or battery acid), and values above 7 are alkaline/basic (like bleach or soap).