How long until the cap? It comes down to two numbers: total XP remaining and how fast you earn it. This calculator builds the remaining XP from an escalating per-level curve and converts it into days at your real play rate.
How it works
Starting from the XP needed at your current level and a per-level growth factor
g, the XP to clear each subsequent level grows geometrically. The totals are:
xp(level k) = baseXP × g ^ (k − current)
total XP = Σ xp(level k) for k = current … cap − 1
total hours = total XP / xp per hour
days = total hours / hours per day
A growth factor above 1 captures the way levels stretch out near the cap; set
g = 1 if your game uses a flat requirement per level.
Example and tips
From level 70 to a cap of 80 with a base requirement of 1,000,000 XP, a 1.1 growth factor, earning 800,000 XP/hour and playing 3 hours/day, the remaining XP sums to roughly 16 million, about 20 hours, or just under 7 days. The forecast is only as good as your XP-per-hour figure — time one real session and use that number.