The main beaches plus clear-water Ko Larn
Ordered from the most convenient in-town beach to the island with the clearest water — pick by what you actually want.
1
Pattaya Beach is the main beach in the centre, a crescent roughly 3 km long running along Beach Road — walk a few minutes from your hotel and you're on the sand. Malls, restaurants, bars, markets and nightlife ring the beach, so it's the most convenient choice if you don't want to travel anywhere. The trade-off is that it's the busiest and most crowded beach, with boats and jet-skis working close to shore, so the water isn't especially clear and you have to watch the boat lanes in places. It suits people who want a lively atmosphere and convenience more than a full day swimming in clear water. In the evening it's a fine spot to stroll the seafront and catch the sunset.
2
Jomtien sits just south of Pattaya Beach over Pratumnak Hill — a long, wide ribbon of sand roughly 6 km long that feels far more open and less crowded than central Pattaya. The gradient is gentle and there's plenty of space, which makes it a good fit for families with kids, anyone who wants room to walk, and watersports like windsurfing and kitesurfing that are popular along here. The seafront has restaurants, hotels at every price point and plenty of sea-view condos. To be straight with you, the water here is still the Gulf, not island-clear, but it's calmer and easier to swim than the in-town beach. It's the one to choose if you want a relaxed beach without the bustle.
3
Wong Amat is the northernmost beach in the Naklua area, and it feels clearly different from the in-town beaches — quieter, less crowded, and lined with upmarket resorts and condos. The sand is whiter than central Pattaya Beach and the water looks a touch cleaner, since it's away from the city-centre boat lanes. It suits couples, honeymooners, or anyone who wants a calm stay while still being a 10 to 15 minute drive from town. The trade-off is that restaurants and nightlife aren't a walk away as they are at Pattaya Beach — you'll need a ride out. If you like quiet and a more refined feel, this fits a proper relaxing trip.
Cosy Beach is a small beach tucked onto Pratumnak Hill between Pattaya and Jomtien — the one locals know has clearer, calmer water than the city beaches, because it sits in a sheltered spot away from the boat lanes. It's short, but the sand is soft and the water is fairly clean, with a handful of resorts and seafront cafés and a laid-back, semi-private feel. It's a good pick if you want a quiet beach close to town without taking a boat out to an island. The trade-offs are that the beach is small and parking is limited, so it can get busy on weekends; part of the way down runs in front of a hotel, but the beach itself is still public and you can walk down.
5
To see genuinely clear water, you have to head offshore — and Ko Larn is the island off Pattaya where the sea is in a different league from the in-town beaches. Take the ferry from Bali Hai Pier, about 45 minutes (~฿30), or a faster speedboat. The island has several beaches to choose from: Tawaen is the liveliest, with a full range of watersports and plenty of restaurants; Samae and Nual are quieter, with lovely clear water for an easy day lying on the sand. Go early to beat the crowds and to get back before the last afternoon ferry fills up.
Pattaya isn't only beaches — once you've done the sand and want a change of scene, head up Pratumnak Hill to the Pattaya City Sign viewpoint, which looks over the whole sweep of Pattaya Bay, with the Big Buddha at Wat Phra Yai nearby. Or visit the Sanctuary of Truth, the hand-carved all-teak temple by the sea over towards Wong Amat. In the evening, Jomtien beach and several rooftop bars make good sunset spots. We've written each of these up in detail — pick where to read on from the links below.