Exponential Calculator: exp(x) = ex
Use this calculator to compute the natural exponential function for any real input value.
What is the exp function?
The exp function is the exponential function with base e, where
e ≈ 2.718281828. In math notation, it is written as:
exp(x) = ex
This is one of the most important functions in mathematics, statistics, engineering, finance, and computer science. It appears naturally in growth and decay models, compound interest, probability distributions, and differential equations.
How to use this exp function calculator
- Enter any real number for
x. - Choose how many decimal places you want to display.
- Click Calculate exp(x).
- Read the standard decimal output and scientific notation output.
If your value is too large, the result may overflow to infinity. If your value is very negative, the result may underflow toward zero. The calculator reports these cases clearly.
Why exp(x) matters
1) Continuous growth and decay
Many real-world systems change proportionally to their current value. Population growth,
radioactive decay, and charging/discharging processes are common examples. The solution
frequently includes ekt, where k is a rate constant.
2) Finance and compounding
In continuous compounding, the future value formula is:
A = Pert.
Here, P is principal, r is annual rate, and t is time.
The exp function gives the exact compounding factor.
3) Statistics and machine learning
The exp function appears in logistic regression, softmax, Gaussian distributions, and likelihood models. Because it transforms values into strictly positive outputs, it is often used to model probabilities and rates.
Quick examples
exp(0) = 1exp(1) = e ≈ 2.71828183exp(-1) ≈ 0.36787944exp(2) ≈ 7.38905610exp(5) ≈ 148.41315910
Relationship to the natural logarithm
The inverse of exp(x) is the natural logarithm:
ln(y). These identities are fundamental:
ln(exp(x)) = xexp(ln(y)) = yfory > 0
This inverse relationship is why exponential and logarithmic calculations are often used together.
Numerical behavior: overflow and underflow
On most JavaScript engines, Math.exp(x) overflows to Infinity around
x > 709.78. For very negative values (roughly x < -745),
results are so close to zero that they underflow to 0.
This is normal floating-point behavior and not a calculator bug. Scientific notation helps interpret very large and very small values more clearly.
FAQ
Is exp(x) the same as e^x?
Yes. They are exactly the same function written in different notation.
Can x be negative?
Absolutely. Negative inputs produce values between 0 and 1.
Why do I get Infinity?
Your input is too large for standard floating-point representation. Try smaller values or use logarithmic transformations in your model.
What is expm1(x)?
expm1(x) computes exp(x)-1 with improved precision for tiny values of
x. This can reduce rounding error in scientific calculations.