How is chances of invasion calculated? does anyone know?

I just tried to take a planet, It has 430 defence and 150 attack, I have 1078 attack and 497 defence, but only had a 46% chance of success. IMO thats just terrible, I have over seven times the planets attack, but less than 50% chance of taking it.

viewtopic.php?f=4&t=7514

The formula in that thread appears to be quite accurate you can try crunching your numbers through it.

On a side note your attack vs planet attack does not seem important the planets invasion defense is a combination of the planets attack and defence vs invaders attack power.

Thanks for the link

I put the numbers in and it says i should have had a 84% chance

EDIT

Invasion defence is defence plus attack? in that case its more like 62% chance, but even so, thats more than what i had.

Yes i'm pretty sure that Dan has confirmed invasion defense is the planets attack & defense

Unfortunately the formula is the best guess but does seem accurate in many instances. You also have to take into account the planets defenses including legion bonus your post doesnt make clear if thats the case, plus the invasion defense from special buildings such as lazuli pylons which don't appear on the planet stats, but contribute to invasion defense.

He didnt have any special buildings on, and if i stop being an idiot, and use the invasion defence after the legion bonus, the equation is correct.

sorry I have been a bit of an idiot, forgot so many things thanks for the help.

You have to put your combined attack add the special bonus attacks from modules psionic amplifiers, lazuli mind controlelrs , etc, and add any spec structures like solider outposts , lazuli pylons to the formula, and don't forget to include artifact buffs.