Named 'Turtle Island' for the sea turtles that once nested on its shores, Koh Tao is the smallest of the three Gulf islands. It has become the world's most popular destination for scuba diving certification, with more PADI certificates issued here than anywhere else. The island covers just 21 square kilometers of granite boulders, coral reefs, and jungle.
Koh Tao barely changes season: around 28°C most of the year.
It rains all year — about 1432 mm in total, from 330 mm in November down to 22 mm in February — so there is no dry stretch to aim for.
Wind is a factor: July averages 20 km/h, enough to notice on a terrace or a bike. Air quality is worth watching: January averages an AQI of 66, while September clears to 34.
Daylight is steady all year, around 12.0 hours a day.
For what you're after, the best months in Koh Tao are June – September. Expect fast internet (218 Mbps) and a low cost of living (about €750 a month).
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