How to calculate probability?

[Tirs]

Actually, the theme of the title. I need some algorithm to calculate the probability actions, for a given stats and difficulty... in percents. Considering the stunts and powers, of course. If there is something like that - I would very appreciate a link, if there isn't... so, I'll have to remember the math

[zaboron]

https://en.wikipedia.org/wiki/Fate_(role-playing_game_system)#/media/File:FUDGE_4dF_probability.svg

[Haru]

That's true for simple rolls. For opposed rolls you get a spread of 8dF (2*4DF) +- the difference between the two skills. Add modifiers by powers if necessary.

8dF:
http://anydice.com/program/6e32

[Tirs]

Thank you)) Ijust want to compare some templates from different settings. That's why I need to percentage.

[Amelia Crane]

The probabilities on fudge dice in ratios and percentages are these:

+4: 1 in 81 = 1.23% (Only roll that can get +4 is ++++)
+3: 4 in 81 = 4.94% (Only rolls that can get +3 are the 4 orderings of +++0)
+2: 10 in 81 = 12.34% (Only rolls that can get +2 are the 4 orderings of +++- and the 6 orderings of ++00)
+1: 16 in 81 = 19.75% (only rolls that can get +1 are the 4 orderings of +000 and the 12 orderings of ++-0)
0: 19 in 81 = 23.46% (only rolls that can get 0 are 0000, the 6 orderings of ++--, and the 12 orderings of +-00)
-1: 16 in 81 = 19.75% (the negatives have the same numbers of results as the positive ones, but with opposite signs on the dice)
-2: 10 in 81 = 12.34%
-3: 4 in 81 = 4.94%
-4: 1 in 81 = 1.23%

I figured these might be nice to have because the link just showed a chart that you may not be able to extract exact data from.