LOGEST Function in Excel: Exponential Curve Fit

⏱ 1 min readUpdated 28 September 2026

StatisticsLevel: ExpertAvailable in: Excel 2007+

In this article
  1. Syntax
  2. Examples
  3. Example 1
  4. Related functions

LOGEST fits y = b·mˣ and returns m (the growth factor) and b. m of 1.05 means 5% growth per period.

Syntax

=LOGEST(known_ys, [known_xs], [const], [stats])
Argument What it means
known_ys Positive values.

Examples

Example 1

=INDEX(LOGEST(C2:C13, A2:A13), 1) - 1

Average monthly growth rate of sign-ups.

GROWTH · LINEST

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