It's important to clarify that the "brightest" stars can be tricky to define. Brightness depends on how far away the star is from us, and also its inherent luminosity.

Here are the top 20 brightest stars in the sky by apparent magnitude, which is how bright they appear to us from Earth:

1. Sirius (Alpha Canis Majoris)

2. Canopus (Alpha Carinae)

3. Arcturus (Alpha Bootis)

4. Vega (Alpha Lyrae)

5. Rigil Kentarus (Alpha Centauri)

6. Capella (Alpha Aurigae)

7. Procyon (Alpha Canis Minoris)

8. Achernar (Alpha Eridani)

9. Betelgeuse (Alpha Orionis)

10. Hadar (Beta Centauri)

11. Altair (Alpha Aquilae)

12. Aldebaran (Alpha Tauri)

13. Spica (Alpha Virginis)

14. Pollux (Beta Geminorum)

15. Fomalhaut (Alpha Piscis Austrini)

16. Deneb (Alpha Cygni)

17. Regulus (Alpha Leonis)

18. Castor (Alpha Geminorum)

19. Bellatrix (Gamma Orionis)

20. Elnath (Beta Tauri)

Important Note:

* Rigil Kentarus is actually a binary star system, so its brightness is combined.

* Betelgeuse is a variable star, meaning its brightness fluctuates.

* Sirius is the brightest star in the sky due to its close proximity to us.

There are many other bright stars that are visible to the naked eye, but these are the top 20 in terms of apparent magnitude.