Satellite view of Koh Tao with approximate depth contours every 10 m

Koh Tao in May

May is peak season in Koh Tao. Expect water around 31 °C at the surface and 31 °C at depth, with about 28 m of visibility.

Season
Peak season
Water
31 °C
Visibility
28 m
Waves
0.4 m
Species likely
381
Best sites for May AprilJune
Koh Tao from Sentinel-2, 1 December 2025 · Contains modified Copernicus Sentinel data 2025; depth contours approximate (NOAA ETOPO 2022)
May at a glance

What May is like in Koh Tao.

Month grade from logged dives across 23 sites: visibility, sea state and sightings. Tap a month to compare.

Divegrade month grade, 0 to 10Best monthsOther months
May · Peak seasonOne of the best months here

Surface 31 °C, at depth 31 °C, visibility 28 m, waves about 0.4 m.

Peak seasonBest: March, April

Compare Koh Tao in March or see the whole year on the Koh Tao page.

Where to dive in May

Best dive sites in Koh Tao in May.

Ranked by Divegrade score for May. Each line shows the site's May conditions where divers have logged them.

Interactive map loads here. Every site on it is also listed on this page.

  1. 01Chumpon Pinnacle29 m viz · 31 °C · Advanced · 12-45 m8.2
  2. 02HTMS Sattakut28 m viz · 31 °C · Advanced · 18-31 m7.7
  3. 03Southwest Pinnacle27 m viz · 31 °C · Advanced · 4-40 m7.6
  4. 04Aow Tanote28 m viz · 31 °C · Beginner · 2-20 m7.4
  5. 05Sail Rock25 m viz · 31 °C · Open Water · 0-40 m7.4
  6. 06White Rock28 m viz · 31 °C · Open Water · 2-26 m7.4

Site list photos: (c) portioid, some rights reserved (CC BY), via iNaturalist (CC BY) · Leonard Low from Australia, via Wikimedia Commons (CC BY 2.0), Moon wrasse, taken elsewhere · (c) Jan Ebr & Ivana Ebrová, some rights reserved (CC BY), via Wikimedia Commons (CC BY 4.0) · (c) Jean Jacques Godon, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) Jan Ebr & Ivana Ebrová, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) Kat Lim, some rights reserved (CC BY), via iNaturalist (CC BY) · H. Schlegel, via Wikimedia Commons (PD), Doublebar Rabbitfish, taken elsewhere · (c) ig: underwater.logs, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) luluchouette, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) Dan Schofield, some rights reserved (CC BY), via Wikimedia Commons (CC BY 4.0) · Amada44, via Wikimedia Commons (CC BY SA 3.0) · (c) Gonzalo Ganda Álvarez, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) Shane Austin, some rights reserved (CC BY), via iNaturalist (CC BY).

What you'll see in May

Hongkong Butterflyfish on 7% of dives.

Chance per dive in May across all sites here, from sightings in logged dives.

Also likely in May 377 species · chance per dive

Other months

Peak season: March, April.

All 23 dive sites in Koh Tao

More places to dive

Pair it, or trade up.

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A mobula ray swimming in open blue water, a remora on its back
Mobula rayMobula sp.15 m · Princess Alice Bank, Azores
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