Generally, the fertilized eggs of smaller (less than 8cm) butterflies hatch for 2~4 days, and they can emerge into butterflies in larval stage 1~2 weeks and pupal stage 1 week.
It takes 3~5 days for fertilized eggs, 2 weeks for larvae and 1 week for pupae of butterfly (8~ 15cm).
It takes 4~7 days for fertilized eggs of giant butterflies (above 15cm), ranging from half a month to several months in larval stage to more than one week in pupal stage.
Some species (regardless of size) only reproduce 1~2 generations a year, and the larval stage will be longer and take several months. If the pupa stage meets winter, it will be extended to the next spring.
If the environment is favorable, the cold weather will last longer (the colder the longer) and the warm weather will be faster (not much faster).