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

Koh Tao in April

April is peak season in Koh Tao. Expect water around 30 °C at the surface and 30 °C at depth, with about 27 m of visibility.

Season
Peak season
Water
30 °C
Visibility
27 m
Waves
0.4 m
Species likely
391
Best sites for April MarchMay
Koh Tao from Sentinel-2, 1 December 2025 · Contains modified Copernicus Sentinel data 2025; depth contours approximate (NOAA ETOPO 2022)
April at a glance

What April 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
April · Peak seasonOne of the best months here

Surface 30 °C, at depth 30 °C, visibility 27 m, waves about 0.4 m.

Peak seasonBest: March, May

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

Where to dive in April

Best dive sites in Koh Tao in April.

Ranked by Divegrade score for April. Each line shows the site's April 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 · 30 °C · Advanced · 12-45 m8.1
  2. 02HTMS Sattakut28 m viz · 30 °C · Advanced · 18-31 m7.6
  3. 03Southwest Pinnacle25 m viz · 30 °C · Advanced · 4-40 m7.6
  4. 04Sail Rock24 m viz · 30 °C · Open Water · 0-40 m7.4
  5. 05Aow Tanote27 m viz · 30 °C · Beginner · 2-20 m7.3
  6. 06HTMS Hanhak Sattru Wreck27 m viz · 30 °C · Open Water · 16-28 m7.2

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) · H. Schlegel, via Wikimedia Commons (PD), Doublebar Rabbitfish, taken elsewhere · (c) ig: underwater.logs, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) Kat Lim, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) Gonzalo Ganda Álvarez, 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) Shane Austin, some rights reserved (CC BY), via iNaturalist (CC BY).

What you'll see in April

Sunrise Tentacle Aeolid on 7% of dives.

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

Also likely in April 387 species · chance per dive

Other months

Peak season: March, May.

All 23 dive sites in Koh Tao

More places to dive

Pair it, or trade up.

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Citizen science

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The ocean covers 70% of the planet but is the least-recorded place on Earth. Scientists can't be on every reef. Divers are.

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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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