toolsko

Choose your language

ToolsKo is written in English. Prefer another language? Open a translated version of this public page.

Browser language suggestion: English. You can choose any language below.

Translation opens in a new tab using Google Translate. It receives this public page URL. Automatic translations may contain mistakes; use the original English page for tool inputs, downloads, and generated documents.

Your choice is remembered on this browser when storage is available. Use Language in the header to change it.

Logarithm Calculator

Find log base b of a positive number.

Tool inputs stay in your browser · optional AI search sends your query

Good to know: log_b(x) = ln(x)/ln(b). x and b must be positive; base cannot equal 1. Results use floating-point arithmetic. All calculations stay in your browser.

How to use it (step by step)

  1. 1Fill in the boxes: “Number”, “Base”. Example numbers are already there so you can see how it works; replace them with yours.
  2. 2The result updates instantly as you type (on a phone it is below the boxes).
  3. 3The bold line is the main answer. Tap Copy next to any value to copy it.

Words to know

Logarithm / root
A root undoes a power (the square root of 9 is 3). A logarithm asks “what power gives this number?” (log₁₀ 100 = 2).

More in Math

Distance & Midpoint CalculatorDistance and midpoint between two Cartesian points.Slope & Line Equation CalculatorFind slope and intercept from two points.Two Linear Equations SolverSolve ax + by = e and cx + dy = f.Arithmetic Sequence CalculatorFind the nth term and sum of a constant-difference sequence.Geometric Sequence CalculatorFind the nth term and finite geometric sum.Z-Score CalculatorStandardize a value using mean and standard deviation.