Skip to content
Thailand Frontier

Map of Thailand

Thailand is about 1,600km from the Malaysian border in the south to the Laos one in the north, with a sea on each side of it. Which sea you are on decides your weather, and the map below is the shortest way to see why.

Chiang Mai Bangkok Phuket Krabi Koh Samui
Every pin is a destination with a guide on this site. Outline from simplemaps.com; the pins are projected from real coordinates rather than placed by eye.

Where it sits

West
The Andaman Sea, and Myanmar beyond it
East
The Gulf of Thailand, with Cambodia on the far shore
North and north-east
Myanmar, then Laos across the Mekong
South
Malaysia, down the peninsula

The peninsula is the part that matters for planning. It is narrow enough that Phuket and Krabi are 60km apart, and wide enough that Phuket and Koh Samui are on opposite coasts with seasons three months out of step.

Computed, not estimated

How far apart they actually are

The straight line is calculated from the coordinates each place's climate was measured at. The journey is the quickest checked way of making it, which is a different number and the one that decides an itinerary.

  • Chiang Mai to Phuket 1213km no checked route
  • Chiang Mai to Krabi 1190km no checked route
  • Chiang Mai to Koh Samui 1037km no checked route
  • Bangkok to Phuket 695km 1h 30m by flight
  • Bangkok to Krabi 654km no checked route
  • Bangkok to Chiang Mai 582km 1h by flight
  • Bangkok to Koh Samui 475km 1h 5m by flight
  • Phuket to Koh Samui 261km 55m by flight
  • Krabi to Koh Samui 200km no checked route
  • Phuket to Krabi 70km 1h 30m by ferry

Straight-line distances are great-circle, so they are shorter than any road or any flight path. Every route we have checked

The two coasts, and which islands are on which

The Andaman, on the west

Phuket, Krabi, Koh Phi Phi, Koh Lanta, Khao Lak, Koh Lipe

Dry from December to March, wettest in October. Limestone karsts, the deepest water and the diving. This is the coast most people picture when they picture Thailand.

Phuket guide

The Gulf, on the east

Koh Samui, Koh Phangan, Koh Tao

Dry from January to September, wettest in November. It runs three months behind the Andaman, which is why it is the answer for a northern summer and the wrong answer for November.

Koh Samui guide

The two are about 250km apart and share almost nothing about their weather. See it month by month

Four regions