I don't want to just recycle a website, but I think the following is a pretty good document. http://www.statisticshowto.com/probability-and-statistics/f-statistic-value-test/

If you're using R you might check these:

http://www.r-tutor.com/elementary-statistics/probability-distributions/f-distribution

https://stats.stackexchange.com/questions/91089/p-value-of-f-test-to-compare-two-variances-var-test-in-r

https://stackoverflow.com/questions/21433528/calculation-p-values-of-a-f-statistic-with-r

Best of luck,

Caleb

Thank you Sir . unfortunately I use SPSS only.

If you know the computed f and tabulated f you can have an idea of a range within which p falls. If for example f1 < f

Rami,

How about Excel? Check this YouTube out for clear instructions / steps.

https://www.youtube.com/watch?v=HWuojFZOigA

Cheers,

Caleb

In R, you can calculate p-value by:

1-pf(Fvalue, df1=v1, df2=v2)

Hope this helps.