Ton Sai is a beach in Krabi Province, Thailand, offering a combination of inexpensive accommodation and great rock climbing routes that make it popular with both backpackers and climbers alike. Compared to neighbouring Rai Leh and Ao Nang it's relatively rough around on the edges; in particular, the beach gets unsuitable for swimming and becomes quite rocky as the tide goes out. But this only happens for about ten days a month. The rest of the time the beach is suitable for swimming.
Current (2023) Tonsai is separated into two parts. Most of the beach front is used by a site where a large luxury ressort was planned, but never actually built. Only a small part is now used by the pricey Tinidee Hideaway Tonsai Beach. Still, the whole area is surrounded by a concrete wall. Next to it is the Tonsay Bay Resort with two restaurants, some shops and a beach bar. All the resorts which were on the beach front until 2014 were moved up the hill behind the wall. There is one main road starting on the north-western beach going there. However, the path going through the Tonsay Bay Resort is connected to the upper road as well by a security gate, which is almost always open.
If you want to listen to the constant buzzing of long tail boats racing between Aonang Beach, Railay Beach and Tonsai Beach this is the place for you.