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

Koh Tao in December

December is outside the peak season in Koh Tao (best: Mar-May). Expect water around 28 °C at the surface and 28 °C at depth, with about 18 m of visibility.

Season
Off peak
Water
28 °C
Visibility
18 m
Waves
0.7 m
Species likely
445
Best sites for December NovemberJanuary
Koh Tao from Sentinel-2, 1 December 2025 · Contains modified Copernicus Sentinel data 2025; depth contours approximate (NOAA ETOPO 2022)
December at a glance

What December 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
December · Off peakOutside the best months (Mar-May)

Surface 28 °C, at depth 28 °C, visibility 18 m, waves about 0.7 m.

Peak seasonBest: March, April, May

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

Where to dive in December

Best dive sites in Koh Tao in December.

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

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

  1. 01Chumpon Pinnacle18 m viz · 28 °C · Advanced · 12-45 m8.1
  2. 02HTMS Sattakut18 m viz · 28 °C · Advanced · 18-31 m7.6
  3. 03Southwest Pinnacle17 m viz · 28 °C · Advanced · 4-40 m7.5
  4. 04White Rock18 m viz · 28 °C · Open Water · 2-26 m7.4
  5. 05Sail Rock17 m viz · 28 °C · Open Water · 0-40 m7.3
  6. 06Aow Tanote18 m viz · 28 °C · Beginner · 2-20 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) ig: underwater.logs, some rights reserved (CC BY), via iNaturalist (CC BY) · (c) Dan Schofield, some rights reserved (CC BY), via Wikimedia Commons (CC BY 4.0) · (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) · Amada44, via Wikimedia Commons (CC BY SA 3.0) · H. Schlegel, via Wikimedia Commons (PD), Doublebar Rabbitfish, taken elsewhere · (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) Shane Austin, some rights reserved (CC BY), via iNaturalist (CC BY).

What you'll see in December

Moon wrasse on 10% of dives.

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

Also likely in December 441 species · chance per dive

Other months

Peak season: March, April, May.

All 23 dive sites in Koh Tao

More places to dive

Pair it, or trade up.

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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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