"Time" magazine checked out the 500 most popular celebrities on Twitter, analyzed each person's posts and found out who the smartest celebs on Twitter are.

None of them Tweet higher than an 8th Grad reading level.

1. Leonardo DiCaprio. The average reading level of his tweets is grade 7.5.

2. Pattie Mallette . . . a.k.a., Justin Bieber's mom. Grade level 7.3.

3. Jimmy Kimmel, grade 7.

4. Ludacris, 6.8.

5. The guys from Green Day, 6.8.

6. Samuel L. Jackson, 6.8.

7. Usher, 6.6.

8. JWoww from "Jersey Shore", 6.6. (Yeah, we were surprised by that one too.)

9-14. Kevin Spacey, 6.5. He's tied with: Wyclef Jean, Eva Longoria, Mike Tyson, Reverend Run, and British singer Jessie J.

15-20. Seth MacFarlane, 6.4. He's tied with Pharrell, Flo Rida, Nicole Richie, Paris Hilton, and Brazilian author Paulo Coelho.

(You can check out the top 50, here.)

Leo is probably at the top of the list is because he's heavily involved in environmental causes, always using big words like "conservation".

Plus, also note that most celebs use interns to manage their twitter accounts, soooooo...

Photo by Anthony Harvey/Getty Images