Koh Phi Phi or Phuket?

On beaches the two are level, and the water is the same warm, clear Andaman Sea. Phi Phi has only a few beaches, framed by cliffs. Loh Dalum is broad but shallow at low tide, so the better swimming is at Long Beach or Laem Tong, and boats go out to Bamboo Island and the coves of Phi Phi Leh.

Phuket gives you far more choice along its west coast. Patong is busy and full of loungers, Kata and Karon are easygoing, Nai Harn and Kata Noi are pretty headland coves, and the long northern stretches are quiet. Phuket also has a bigger hazard. From May to October, monsoon surf and rip currents make many of its bays unsafe, while on Phi Phi the rougher season mostly means cancelled boat trips.

Phuket is far better for anyone who travels to eat. Phuket Town has a local cuisine shaped by Hokkien and Peranakan settlers. You can have dim sum and crab curry with rice noodles for breakfast, braised pork belly, and grilled food at the old-town walking street. There is good seafood at Rawai and a small fine-dining scene as well.

Phi Phi's food comes from a few lanes in Tonsai village, with curries, pizza and burgers aimed at backpackers. The best of it is banana roti from street carts and seafood grilled on the beach in the evening.

Neither island is a culture trip, but Phuket at least gives you a worthwhile half day. You can walk the pastel shophouse streets of Phuket Town's old quarter, visit Wat Chalong and the Big Buddha above Chalong Bay, and learn about the Burmese siege of 1785 at the Thalang National Museum.

Phi Phi has almost nothing to visit. There is a small tsunami memorial, and you can see the swiftlet-nest cliffs of Viking Cave from a passing boat.

Phuket has more nightlife and more kinds of it. Bangla Road in Patong is a long strip of clubs, neon bars and go-go bars that runs until the small hours. Beyond it there are sunset sessions at west-coast beach clubs, relaxed bars at Kata and Karon, and shophouse cocktail bars in Phuket Town where many of the customers are Thai.

Phi Phi offers one kind of night out, and does it with energy. Loh Dalum turns into a beach party with mats, fire shows, dance music and drinks served in buckets, while reggae bars fill up in the village. It is young and loud, and if you want variety you will not find it here.

On nature the two are level, but they offer it at different scales. On Phi Phi the limestone walls rise straight from the water around you. The viewpoint over the two bays, Pileh Lagoon, the soft coral at Bida Nok and the blacktip sharks at Shark Point are all close by. The trade-off is that the island is small and its reefs show wear from heavy boat traffic.

Phuket is a base for a wider area. You can kayak through the caves of Phang Nga Bay, dive the Similans in season, and visit the rainforest of Khao Phra Thaeo with its gibbons and waterfalls. Each of these takes more travel to reach.

Phuket has much more within a day's reach, and one of its classic outings is Phi Phi itself. Boats also go to the stilt village of Koh Panyee and the rural Koh Yao islands. The bridge to the mainland opens up Phang Nga, Krabi and the old tin town of Takua Pa by road.

From Phi Phi, nearly everything means a ferry. Koh Lanta and Railay are reasonable outings, but Phuket Town makes a long day. Most excursions from Phi Phi are boat tours to empty bays, so towns and heritage are better planned as separate stops on a wider route.

Phuket works much better with children. Its big resorts are designed for families, and there are water parks, an aquarium at Cape Panwa and snorkelling trips to fill the days. Its weak points are the dangerous surf in the monsoon months and busy roads with few pavements.

On Phi Phi, a family needs to stay at Laem Tong or one of the quiet northern beaches, where the water is calm. There are no cars, which helps. The village is noisy and crowded, the paths to the outer beaches are steep and unlit, medical care is basic, and the ferry over can be rough.

Phi Phi is the easier of the two once you are there, because there are no cars at all. Tonsai and Loh Dalum are a few minutes' walk apart, and longtail boats or hill paths cover the rest. The catch is that you need a ferry to get there, plus a boat transfer if you stay in the north.

Phuket has no rail and only basic buses that run from town out to the beaches, not between them. That leaves taxis and tuk-tuks on fixed fares, ride-hailing or a hired scooter. Its hilly roads get congested and are risky for inexperienced riders.

Phuket is the only one of the two where shopping is worth doing. It has large malls near Phuket Town and in Patong, tailors who make clothes in a few days, and pearls from local farms. The better finds are at the Sunday walking street and in the old-town boutiques selling batik and Peranakan-style goods.

On Phi Phi you can buy beachwear, sunscreen and snorkel gear in the village lanes, and little else. It is best to stock up before you take the ferry.

Phuket is easier on the budget. Street food and markets in Phuket Town are cheap, and there are simple guesthouses at every beach, although taxis and high-season resorts push costs up.

On Phi Phi, everything comes in by boat. Dry-season rooms cost far more than on the mainland, and the island entry fee, longtail rides and drinks add up quickly. Backpackers in dormitories get by, but even they will notice it costs more than most of Thailand.

Neither island has theatre or concerts of any substance, but Phuket at least has a few shows to book. There are long-running cabaret revues in Patong, a large cultural show with dancers, and Thai boxing nights. On Phi Phi, entertainment is limited to fire dancers on the sand and cover acts in the village bars.

Phuket is the clear choice for a restorative trip. You can have a Thai massage almost anywhere, there are resort spas in open pavilions over the sea, and around Chalong there are yoga stays, detox programmes and Muay Thai camps. Mai Khao, Bang Tao and Nai Harn are quiet places to stay.

On Phi Phi you will find massage on beach mats and in village parlours, plus a few resort spas in the north. Your stay will only feel restful if you sleep at Laem Tong or the remote eastern bays, well away from Tonsai's late music.