Formulas / FORECAST
Predicts values based on a linear trend
FORECAST(x, known_y's, known_x's)
  • x - the data point
  • known_y's - the dependent array or data range
  • known_x's - the independent array or data range


  • =FORECAST(B13,sales,periods)

    The FORECAST function is used to predict a future value, such as sales values over different periods.This takes the values from the named range sales (located in cells C5:C12) and the named range periods (located in cells B5:B12) and uses them to calculate the predicted value for cell D13.


The FORECAST function calculates a future value based on existing values using linear regression. It produces a y-value for a given x-value, allowing for accurate predictions of future values.

  • Starting with Excel 2016, FORECAST has been replaced with FORECAST.LINEAR, which will eventually be deprecated.
  • FORECAST returns a #VALUE! error if the given x value is not numeric.
  • FORECAST returns an #NA error if the sizes of the known_ys and known_xs are not the same.
  • FORECAST returns a #DIV/0! error if the variance of the known_x values equals zero.

Frequently Asked Questions

What is the FORECAST function?
The FORECAST function is an old function that has been replaced with FORECAST.LINEAR in Excel 2016. It returns a predicted value based on existing values, using the equation A+Bx.
How is the syntax of FORECAST different from FORECAST.LINEAR?
The syntax of FORECAST.LINEAR is the same as FORECAST.
What errors are returned by FORECAST and FORECAST.LINEAR?
  • FORECAST returns a #VALUE! error if x is non-numeric.
  • For Excel 2016, FORECAST.LINEAR returns a #N/A error if known_y's or known_x's is empty. It also returns a #N/A error if known_y's has more data points than known_x's, or vice versa.
  • FORECAST and FORECAST.LINEAR return the #DIV/0! error if the variance of known_x's is zero.

Make Better Decisions
With Data

Analyze data, automate reports and create live dashboards
for all your business applications, without code. Get unlimited access free for 14 days.