Free · Exponents and logarithms

e to a Power & Natural Exponent

Calculate e raised to a real exponent and recover the exponent from a positive result, with a separate rounded display.

Calculator inputs

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Enter the known values in the units shown. Results update as you type.
Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
Use the worked example to check the method. Reset restores the starting fields.

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e⁰ = 1. e¹ is approximately 2.718281828459045, and its five-decimal display is 2.71828.

Result = eˣ; exponent = ln(result)

Enter these known values and leave the other values blank.

The exponent may be negative, zero or positive, with the retained upper bound of 600. Results must be positive for reverse logarithms.
The result sentence gives a five-decimal display of the same underlying value. A rounded display of zero does not make the mathematical exponential zero.
Values use 64 significant digits internally; extremely small or large magnitudes can exceed practical numeric limits.

No. It is positive, though an extremely small value can round to zero in a short decimal display.

Yes. Enter the result and the calculator uses its natural logarithm.

The real exponential and its alternate rounded-display field must be positive when used as reverse inputs.