How do you know if a strain that you have is Auto Flower?

Hello community! Just as the title asks; how can you tell if a strain in your garden (bagseed or clones) is an auto flower breed? Is there any compendium of all the breeders different strains and flower lengths?
Help appreciated! Thanks everyone.
Greggos

Auto flowers varieties automatically switch from vegetative growth to the flowering stage with age, as opposed to the ratio of light to dark hours required with photoperiod dependent / short-day strains. Many autoflowers will be ready to harvest in less than 10 weeks from seed. Dwarf varieties can have comparatively short stature while still giving decent yield. Conversely "super autos" can take over 100 days to mature and can reach over 6 feet tall. Autoflowers are one of the fastest growing strain varieties for sale on the market today.

So what it means it will flowers by age not by photoperiod, if it's a real autoflower it will flower under 24hrs of light.