Natural Log Calculator
Calculate the natural logarithm (ln) of a number, base e.
- Free to use
- Accurate results
- No registration required
- Works on all devices
Enter a value to calculate its natural logarithm (ln).
Your result
4.605
ln(value)
AI explanation
Formula
ln(value) = log base e of value, where e ≈ 2.71828Worked example
Natural log of 100
| Field | Value |
|---|---|
| Value | 100 |
| ln(value) | 4.60517019 |
Assumptions
- Value must be positive — the natural log is undefined for zero or negative numbers.
Frequently asked questions
What is the natural logarithm?
The logarithm base e (Euler's number, ≈2.71828) — it appears throughout calculus, compound growth, and exponential decay formulas.
What is ln(e)?
1 — because e¹ = e, by definition.
Is this different from log base 10?
Yes — see the Logarithm Calculator for a base-10 (or any other base) logarithm instead.