this is the formula used in RPG Maker XP for working out how much EXP you need to reach the next level

EXP to next Level = B * ((L+4)^(I/100))/(5^(2.4+I/100))

L = current Level

B = Base, i'm using 150

I = inflation, i'm using 50

eg. 150 * ((3+4)^(50/100))/(5^(2.4+50/100)) = 398

now i can work out how much EXP i need to reach Level X from Level 1 by summing the value of the above formula from 1 to X-1 so if i was ta level 1 and wanted to go to level 8 i would need to sum 105, 255, 398, 586, 825, 1120, 1476 to get 4809, this is simple enough

what i want to work out is what my level is given the exp i have, one way if i was programming it is to just use a recursive loop and break out of it when the sum of the exp is greater than my current, i want to avoid using a loop cause what if i'm level 8987, the loop could take a while so i'd rather use a formula that'll output the level, i'm not fused if it get a decimal like 5.26 cause then i can either chop of the .26 or just say that you have 26% of the exp needed to level up

so what do i need to do in order to get my current level based from how much exp i have, i know that just reserving the above formula isn't enough

i should also note that i'm not using RPG Maker XP here, it's for a different system where i only have stored the EXP and not the level