Any age honestly she has a style that is both sophisticated and whimsical yes she is known for he bright colors and crazy styles but she does have some purses that are more tamed but still very very stylish!
All the girls that are writing making me feel old lol.. Hey I wear her stuff too alright! And I'm 31plus yrs old. I think any chicks can wear her stuff. She has a lot of cute necklace like for little girls and also an older woman can wear it too.
I'm a sophmore in college and I currently use a Betsey Johnson backpack. I am very girly though so I enjoy the fun prints and bright colors, but other 20 years olds may not. On average, Id say high school age.
I would venture to say high school freshman and up. I wouldn't do younger ages because of some of her price points. But the clothes and their designs wouldn't be inappropriate for a younger age, such as 13.