Logarithm Calculator
Calculate natural logarithm (ln), common logarithm (log10), binary logarithm (log2), and custom base logarithms. Free online log calculator.
Antilogarithm (Inverse Logarithm)
Common Logarithm Values
| x | ln(x) | log₁₀(x) | log₂(x) |
|---|---|---|---|
| 1 | 0.0000 | 0.0000 | 0.0000 |
| 2 | 0.6931 | 0.3010 | 1.0000 |
| e ≈ 2.718 | 1.0000 | 0.4343 | 1.4427 |
| 10 | 2.3026 | 1.0000 | 3.3219 |
| 100 | 4.6052 | 2.0000 | 6.6439 |
| 1000 | 6.9078 | 3.0000 | 9.9658 |
Logarithm Formulas
Change of Base: logb(x) = ln(x) / ln(b)
Product Rule: log(xy) = log(x) + log(y)
Quotient Rule: log(x/y) = log(x) - log(y)
Power Rule: log(xn) = n × log(x)
Inverse: blogb(x) = x
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