Math
Negative Log Calculator
Compute −log₁₀(x), as used for pH and pKa.
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The negative logarithm turns very small numbers into convenient positive values — the idea behind pH.
The math behind it
result = −log₁₀(x). Smaller x gives a larger result; each factor of 10 changes it by 1.
Worked Example
−log₁₀(0.0001) = 4 (a hydrogen-ion concentration of 10⁻⁴ means pH 4).
Frequently Asked Questions
Why use it for pH?
Concentrations span many orders of magnitude; the negative log compresses them into a 0–14 scale.
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