A nude beach, sometimes called a clothing-optional or free beach, is a beach where users are at liberty to be nude. Nude beaches usually have mixed bathing. Such beaches are usually on public lands, and any member of the public is allowed to use the facilities without membership in any movement or subscription to any personal belief. The use of the beach facilities is normally anonymous. Unlike a naturist resort or facility, there is normally no membership or vetting requirement for the use of a nude beach. The use of nude beach facilities is usually casual, not requiring pre-booking. Nude beaches may be official (legally sanctioned), unofficial (tolerated by residents and law enforcement), or illegal.

In some countries, nude beaches are relatively few and are usually at some distance from cities, and access is at times more difficult than at a regular beach and the facilities at these beaches tend to be very basic with a few notable exceptions.

In other countries, like Denmark, most beaches are clothing-optional. Nude swimming is one of the most common forms of nudity in public. A nude beach should not be confused with a topless beach (or top-free beach), where upper body clothing is not required for women or men, although a swimming costume covering the genital area is required for both men and women. A nude beach should be considered as a clothes-free beach.

Nude beaches tend to be separate or isolated physically from non-nude bathing areas.

In other instances people maintain a comfortable space between beach users.

Signage is often used to warn unfamiliar beach users about the specially designated areas on the beach.

This accommodates people who are not comfortable with nudity, as well as nude beach users who do not like to be watched by clothed individuals, particularly those engaged in voyeurism.

Most nude beaches become accepted after many years of use as nude beaches.

Many are "unmanaged" beach areas that have been adopted by the local users in an effort to maintain the beach's "quality".

Others' right to existence has been recognized as such by the appropriate local authority, and are termed "official" (although not necessarily legitimate).

There are several categories of nude beaches:

Most beaches around the world, including nude beaches, are on public lands.

That means that although private resorts and hotels that adjoin a beach may enclose their property behind fences with controlled access, most countries do not allow private ownership of the actual beach area.

Thus, while a resort can control access and set clothing standards on its property, these standards would not necessarily apply to the beach itself, which remains subject to local laws or customs, and public access to the beach itself usually remains unrestricted.

This applies, for example, to the islands in the Caribbean, Mexico, and Florida.

On the Seven Mile Beach in Negril, Jamaica, for example, though the beach is lined with private resorts with fences down to the sand/waterline, the beach itself is open to the public. Though actual clothing standards vary from resort to resort, the beach area is officially designated as "topfree", and public access is unrestricted.

The International Naturist Federation has developed a code of conduct, or etiquette, for use by member organizations. The INF nude beach etiquette requires the avoidance of all forms of sexual harassment and sexual activity, such as masturbation or sexual intercourse. Predatory behavior is not permitted, nor is unauthorized photography.^[3] In general, the standards call for the respecting of the privacy of other visitors. Staring is frowned upon by rule and social pressure.^[4]

However, unlike nudist resorts and hotels, which can enforce standards of conduct on their properties promptly and effectively, most nude beaches are on public lands, making the enforcement of standards of nude beach etiquette a more personal matter, subject to the deterrence of local laws.

The standards of conduct take different forms in different countries.

Other than the fact that people using a nude beach expect to find naked people on the beach, most other local laws and customs continue to apply.

During a 1936 Adriatic cruise, King Edward VIII and his mistress Wallis Simpson stopped at a beach on the island of Rab where the King obtained a special permission from the local government to swim naked, thereby designating it the world's first official nude beach.^[5] Nude beaches became popular in the 1950s along the French coast^[6] and have since spread around the world, though they are still few and far between. Some nude beaches are part of a larger nude area, such as the Cap d'Agde area. Most beaches in Denmark^[7][8] and some beaches in Norway^[9] are clothing-optional. In Germany there are clothes optional sunbathing areas in public parks, e.g., Munich^[10] and Berlin.^[11] Beaches in some holiday destinations, such as Crete, are also clothing-optional, except some central urban beaches.^[12] There are two centrally located clothes-optional beaches in Barcelona.^[13]

Though free beaches developed separately from national naturist bodies, some of these bodies have taken an interest and helped to protect them legally, and through the publication of guidelines of acceptable behaviour.^[14] In North America, the Free Beach Movement was the name of a group that was opposed to the direction of the official nudist organisation, the American Association for Nude Recreation, and set up the rival body The Naturist Society. Clothes free organizations and free beach associations, such as the Naturist Action Committee, lobby for the removal of laws which prohibit nude swimming and sunbathing or the increase in the number of nude beaches and sometimes to improve the amenities at nude beaches.