Math
Logarithm Calculator
Compute log_b(x) for any positive base — 10, e (natural), 2, or a custom base.
Inputs
Logarithm Calculator
Result
log_10(1000)
3
- Antilog check bʸ
- 1,000
- ln(x)
- 6.90775528
- log₁₀(x)
- 3
How it's calculated
log_b(x) = ln(x) / ln(b). Inverse: b^(log_b x) = x.
Common questions
What's the difference between log and ln?
log usually means base 10; ln means the natural log, base e ≈ 2.71828.
Why can't the value be zero or negative?
Logarithms of non-positive numbers are undefined in real numbers.
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