Public nudity is nudity in a public place, or in a private place that is visible to those in a public place. Nudity on privately owned property onto which the general public is free to enter (a shopping mall, for example), is also considered public nudity. Nudity in the privacy of a person's home or grounds is not considered public nudity, nor is nudity at privately-owned facilities where nudity commonly takes place (gyms, locker rooms, saunas, or nudist clubs, for example). Naturism is a movement that promotes social nudity in natural settings; most of such nudity takes place on private property.

Not all people who engage in public nude events see themselves as naturists or belong to traditional naturist or nudist organizations.

Some activists, such as Vincent Bethell, claim that association with naturism or nudism is unnecessary.

Others will point out that many people who participate in events such as clothing-optional bike rides or visit clothing-optional beaches do so casually and without association or formal affiliation to groups or movements. Activist Daniel Johnson believes that labels and affiliations overly complicate a relatively simple phenomenon, alienate others from a fear of over-commitment or undesirable stereotypes, and thus get in the way of integrating nudity into everyday life.

The social norms or laws of each culture require the wearing of clothes in most situations, but this expectation may be suspended in limited circumstances.

For example, there are many countries which have designated public areas as nude beaches, or where nude bathing is unofficially tolerated. In those places, a person would not face legal prosecution or official harassment merely for being nude.

Outside of those areas, community and legal acceptance of public nudity varies considerably. To avoid offending the public in general, public authorities maintain what are sometimes called "standards of decency". What falls outside these standards are usually termed "indecent exposure", or similar terminology. These standards, however, vary with time and place. If the intent is to draw attention to oneself, it may be referred to as exhibitionism, otherwise it may be to draw attention to a cause (see nudity and protest). There are also some people who disrobe in public to attract publicity to themselves, as a career move, such as some streakers at sporting events. There are also others who spontaneously disrobe in public, as an expression of their freedom and the shedding of inhibitions; an example being skinny dipping.

Some people take part in non-sexual public nude events.

These may be in a naturist resort or club or at a nude beach.

Outdoor nude recreation can take place in private or rural areas, though generally limited to warm weather.

Others practice casual public nudity.

Topfree sunbathing is considered acceptable by many on the beaches of Finland, France, Spain, Italy and most of the rest of Europe (and even in some outdoor swimming pools); however, exposure of the genitals is restricted to nudist areas in most regions.

In the United States, topfree sunbathing and wearing thongs are not common in many areas, but are limited to nude beaches in various locations. It is normally acceptable for men in the U.S. to be barechested or shirtless when engaged in outdoor recreational activities.

Where the social acceptability of nudity in certain places may be well understood, the legal position is often less clear cut.

In England, for example, the law does not actually prohibit simple public nudity, but does forbid indecent exposure.^[1] In practice, this means that successful prosecution hangs on whether there is a demonstrable intention to shock others, rather than simply a desire to be nude in a public place.

Specifically, using nudity to "harass, alarm or distress" others is an offence against the Public Order Act of 1986.

Occasional attempts to prove this point by walking naked around the country therefore often result in periods of arrest, followed by release without charge, and inconsistencies in the approach between different police jurisdictions.

Differences in the law between England and Scotland appear to make the position harder for naked ramblers once they reach Scotland.

Photography of installations of massed nude people in public places, as made repeatedly around the world by Spencer Tunick, claim artistic merit.

It is generally accepted in western countries that a naked human body is not in itself indecent. That principle is reflected, for example, in depiction of the human form in art of various forms.

The lack of appropriate clothing may cause offence to others, giving raise to legal intervention in the form of charges described, for example, as indecent, offensive or disorderly conduct.

This is the position, for example, in Germany^[2] and Spain, although local laws in the latter country can stipulate that public nudity is either restricted or not permitted.

In Barcelona, public nudity used to be regarded as a recognised right, although there have been successful prosecutions for public nudity even there and a local ordinance by the local council in May 2011 empowers the authorities to impose a fine for nudity and being bare chested.^[3] In the Netherlands, public nudity is allowed on sites that have been assigned by the local authorities and other suitable places which effectively means any complaint will cause one to be arrested as a complaint is indication that the place was not "suitable".^[4]

In many countries public nudity is forbidden outright on the basis that nudity is inherently sexual.

Many states of the United States fine offenders on that basis—see Indecent exposure in the United States.^[5] In Arkansas, not only is nudism illegal (even on private property), it is a crime to "promote" or "advocate" (i.e. express a favorable opinion about) nudism.^[6] In many contexts, public nudity has been more accepted, especially at designated areas such as nude beaches and, even in the United States, e.g. during World Naked Bike Ride events or Bay to Breakers. In some states, such as Oregon, public nudity is legal and protected as free speech, as long as there is not the "intent to arouse". In the United Kingdom, nudity per se is not unlawful, but the circumstances surrounding particular episodes of nudity may create public order offences, according to a police spokesman in July 2013.^[7] After repeated arrest, prosecution, conviction in Great Britain, the activist Stephen Gough sued at the European Court of Human Rights for his right to be nude in public outside of designated areas (like nude hiking). Gough's case concerned only charges brought against him in Scotland. The ECHR rejected his complaint in October 2014,^[8] stating that authorities in Scotland had not "unjustifiably interfered with his exercise of freedom of expression", though they did admit that the "acceptance of public nudity in a modern society is a matter of public interest".^[9][10]

Nudity has sometimes been used to attract media and public attention to a cause.

Nudity in protest was used as a tactic by the Doukhobors in the early 20th century, and has been more widely used since the 1960s. Modern slogans include "Disrobe for disarmament", "Nudes, not nukes!", "Naked For Peace", and PETA's "I'd rather go naked than wear fur!".

Public nude protest groups and events include:

Though depictions of nudity have been an aspect of art at all times, contemporary art has extended the use of nudity to non-traditional forms. For example:

Certain activities in public areas are more readily accepted to be done while naked, such as sun bathing and swimming. Everyday activities such as riding a train or bus, shopping, or attending school or work are almost never considered by the public to be appropriate without clothing.

Examples include going nude swimming at hot springs, nude beaches, naked hiking, streaking and even roller skating. Sandy Snakenberg has organized nude skating and rollerblading events in San Francisco, the largest of their kind in the world. Nude beaches are found in many Western countries.

In recent times, it appears that public nudity is becoming more common with nude sporting and other activities being held.

These include naked hiking, canuding (nude canoeing), the World Naked Bike Ride, Bay to Breakers, Solstice Cyclists. Clothing-optional bike rides are becoming regular events around the world.

In 2016 naked dining has become something of a fashion, with naked restaurants opening in London,^[33] Melbourne^[34] and Tokyo.^[35]

Nudity in public, if any, is most commonly non-sexual in nature.

For example, aspects of the Nambassa hippie festivals held in New Zealand in the 1970s are regarded as non-sexual naturism. Of the 75,000 patrons who attended the 1979 Nambassa 3-day counterculture festival, an estimated 35% spontaneously chose to remove their clothing,^[36] preferring complete or partial nudity.^[37]

However, some nudity in public may give rise to controversy.

Some people regard flashing, streaking and mooning as indecent exposure and as sexual public nudity. Similarly, some people regard dogging, exhibitionism, and voyeurism as offensive behaviour.

Burning Man camps range from non-sexual nudity to overtly sexually themed, while the Folsom Street Fair held in San Francisco is a leather and BDSM themed fair.^[38] Nudes-A-Poppin' is an annual pageant in the United States for nude women and men competing in erotic dance.^[39]

In some cultures, toplessness by women in public is considered acceptable, while complete nudity is not.

Although most ceremony and traditions involve dressing up, often with some preferential attire, certain cultural or religious traditions actually prescribe(d) ritual nudity.

For example, ancient Sparta held a yearly celebration from 668 BC called gymnopaedia during which naked youths displayed their athletic and martial skills through the medium of war dancing.^[40] The Adamites, an early Christian sect, practiced "holy nudism", engaging in common worship in the nude. During the Middle Ages, the doctrines of this obscure sect were revived: in the Netherlands by the Brethren of the Free Spirit and the Taborites in Bohemia, and, in a grosser form, by the Beghards in Germany. Everywhere, they met with firm opposition from the mainstream churches.^[41]

This may be symbolic, especially for 'rebirth' to a new life phase, as in the case of baptism (originally taken by an adult, later often as a child - to symbolise the washing away of original sin - and/or at least partially covered up) or certain coming of age rites, such as cow jumping by young men of the East African Hamar people before they are eligible for marriage.

There is a tradition in some neopagan Wiccan covens of ritual nudity, called going skyclad.

In India, Digambara monks reject any form of clothing and practice nudity. Digambara (lit. 'sky clad') is one of the two main sects of Jainism.^[42]

In some hunter-gatherer cultures in warm climates, public nudity (or near-complete nudity) has been, until the introduction of Western culture or Islam, or still is, the social norm for both men and women.^[43]

Complete nudity among men and complete or near-complete nudity among women is still common for Mursi, Surma, Nuba, Karimojong, Kirdi, Dinka and sometimes Maasai people in Africa, as well as Matses, Yanomami, Suruwaha, Xingu, Matis and Galdu people in South America.^[44]

Australian Aborigines before European settlement did not wear clothes in day-to-day life;^[45] but were also ritually exposed as a functional part testing endurance, e.g., to undergo scarification, as was also the case and Sepik River tribes in Papua New Guinea.