pH Calculator

Calculate pH, pOH, or hydrogen ion concentration

Formula: pH = -log[H+]

Where [H+] is the hydrogen ion concentration in mol/L

pH Scale Reference

0 (Acidic) 7 (Neutral) 14 (Basic)
Stomach acid: 1.5-3.5
Lemon juice: 2.0-2.4
Vinegar: 2.4-3.4
Coffee: 4.5-5.5
Pure water: 7.0
Seawater: 7.5-8.4
Baking soda: 8.3-9.0
Bleach: 12.5

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