According to the Speedtest Global Index by Ookla, as of July 2021, the top 10 countries with the fastest average internet speeds are:

1. United Arab Emirates: 190.03 Mbps
2. Singapore: 185.16 Mbps
3. South Korea: 180.28 Mbps
4. Hong Kong: 179.87 Mbps
5. Monaco: 175.62 Mbps
6. Switzerland: 169.38 Mbps
7. Thailand: 159.69 Mbps
8. Romania: 158.65 Mbps
9. Denmark: 157.37 Mbps
10. Spain: 155.93 Mbps

Please note that these rankings can change on a regular basis as internet speeds continue to evolve.