Ice and Fire dragon stats calculator
By stage
How dragons grow
A dragon ages one day per Minecraft day (20 minutes). Its health, bite damage and speed rise in a straight line until day 125 and then stop: 20 to 500 health, 1 to 18 bite damage. It moves up a stage every 25 days, reaching stage 5 on day 100, and its breath attack hits for its base damage times the stage (fire 2, ice 2.5, lightning 3.5), so a stage 5 fire dragon breathes for 10 a hit. Fire, ice and lightning dragons share the same body stats.
Armor is the odd one out: it keeps growing past day 125, and dragon armor adds 1 plus 2 to 10 per piece (10 for dragonsteel). The game caps a creature's armor at 30, which a fully armoured adult reaches easily.