1. Mascara’s shelf life is 4-6 month and you should be especially careful with anything that goes close to your eye. An eye infection is a nasty thing you want to avoid by all means.
2. Eyeliner: if it’s a pencil its shelf life is 1 year and since you always sharpen it you always renew the tip and delete any bacteria on it. But if an oily substance is leaking out of it – throw it away immediately. Liquid eyeliners “live” much less, about 6 months, because microbes can easily breed inside the bottle.
3. Lipstick: on average its shelf life is 8 months but good brands live much longer. If your lipstick started to stick to your lips – don’t use it anymore
4. Powder eye shades and blushes are usually good for up to 2 years, liquid – up to a year.
5. Concealers and compacts are good for 1 year too but pay attention to their smell and consistency. If something changes for the worth – throw them away
6. Brushes: if made of natural hair, they can live forever if you take care of them properly: wash them once a week with warm water and regular soap and let them dry well.
If you want your favorite cosmetic products live longer there is one rule of thumb: decrease sun, heat and humidity exposure!