delivered the opinion of the Court.
The question presented is whether the housing of two inmates in a single cell at the Southern Ohio Correctional Facility is cruel and unusual punishment prohibited by the Eighth and Fourteenth Amendments.
I
Respondents Kelly Chapman and Richard Jaworski are inmates at the Southern Ohio Correctional Facility (SOCF), a maximum-security state prison in Lucasville, Ohio. They were housed in the same cell when they brought this action in the District Court for the Southern District of Ohio on *340behalf of themselves and all inmates similarly situated at SOCF. Asserting a cause of action under 42 U. S. C. § 1983, they contended that “double celling” at SOCF violated the Constitution. The gravamen of their complaint was that double celling confined cellmates too closely. It also was blamed for overcrowding at SOCF, said to have overwhelmed the prison’s facilities and staff.1 As relief, respondents sought an injunction barring petitioners, who are Ohio officials responsible for the administration of SOCF, from housing more than one inmate in a cell, except as a temporary measure.
The District Court made extensive findings of fact about SOCF on the basis of evidence presented at trial and the court’s own observations during an inspection that it conducted without advance notice. 434 F. Supp. 1007 (1977). These findings describe the physical plant, inmate population, and effects of double celling. Neither party contends that these findings are erroneous.
SOCF was built in the early 1970’s. In addition to 1,620 cells, it has gymnasiums, workshops, schoolrooms, “dayrooms,” two chapels, a hospital ward, commissary, barbershop, and library.2 Outdoors, SOCF has a recreation field, visitation *341area, and garden. The District Court described this physical plant as “unquestionably a top-flight, first-class facility.” Id., at 1009.
Each cell at SOCF measures approximately 63 square feet. Each contains a bed measuring 36 by 80 inches, a cabinet-type night stand, a wall-mounted sink with hot and cold running water, and a toilet that the inmate can flush from inside the cell. Cells housing two inmates have a two-tiered bunk bed. Every cell has a heating and air circulation vent near the ceiling, and 960 of the cells have a window that inmates can open and close. All of the cells have a cabinet, shelf, and radio built into one of the walls, and in all of the cells one wall consists of bars through which the inmates can be seen.
The “dayrooms” are located adjacent to the cellblocks and are open to inmates between 6:30 a. m. and 9:30 p. m. According to the District Court, “[t]he day rooms are in a sense part of the cells and they are designed to furnish that type of recreation or occupation which an ordinary citizen would seek in his living room or den.” Id., at 1012. Each dayroom contains a wall-mounted television, card tables, and chairs. Inmates can pass between their cells and the day-rooms during a 10-minute period each hour, on the hour, when the doors to the dayrooms and cells are opened.
As to the inmate population, the District Court found that SOCF began receiving inmates in late 1972 and double cell-ing them in 1975 because of an increase in Ohio’s statewide prison population. At the time of trial, SOCF housed 2,300 inmates, 67% of whom were serving life or other long-term sentences for first-degree felonies. Approximately J.,400 inmates were double celled. Of these, about 75% had the choice of spending much of their waking hours outside their cells, in the dayrooms, school, workshops, library, visits, meals, or showers. The other double-celled inmates spent *342more time locked in their cells because of a restrictive classification.3
The remaining findings by the District Court addressed respondents’ allegation that overcrowding created by double celling overwhelmed SOCF’s facilities and staff. The food was “adequate in every respect,” and respondents adduced no evidence “whatsoever that prisoners have been underfed or that the food facilities have been taxed by the prison population.” Id., at 1014. The air ventilation system was adequate, the cells were substantially free of offensive odor, the temperature in the cellblocks was well controlled, and the noise in the cellblocks was not excessive. Double celling had not reduced significantly the availability of space in the dayrooms or visitation facilities,4 nor had it rendered inadequate the resources of the library or schoolrooms.5 Although there were isolated incidents of failure to provide medical or dental care, there was no evidence of indifference by the SOCF staff to inmates’ medical or dental needs.6 As to violence, the court found that the number of acts of violence at *343SOCF had increased with the prison population, but only in proportion to the increase in population. Respondents failed to produce evidence establishing that double celling itself caused greater violence, and the ratio of guards to inmates at SOCF satisfied the standard of acceptability offered by respondents’ expert witness. Finally, the court did find that the SOCF administration, faced with more inmates than jobs, had “water[ed] down” jobs by assigning more inmates to each job than necessary and by reducing the number of hours that each inmate worked, id., at 1015; it also found that SOCF had not increased its staff of psychiatrists and social workers since double celling had begun.
Despite these generally favorable findings, the District Court concluded that double celling at SOCF was cruel and unusual punishment. The court rested its conclusion on five considerations. One, inmates at SOCF are serving long terms of imprisonment. In the court’s view, that fact “can only accent [u ate] the problems of close confinement and overcrowding.” Id., at 1020. Two, SOCF housed 38% more inmates at the time of trial than its “design capacity.” In reference to this the court asserted: “Overcrowding necessarily involves excess limitation of general movement as well as physical and mental injury from long exposure.” Ibid. Three, the court accepted as contemporary standards of decency several studies recommending that each person in an institution have at least 50-55 square feet of living quarters.7 In contrast, double-celled inmates at SOCF share 63 square feet. Four, the court asserted that “[a]t the best a prisoner who is double celled will spend most of his time in the cell *344with his cellmate.” 8 Id., at 1021. Five, SOCF has made double celling a practice; it is not a temporary condition.9
On appeal to the Court of Appeals for the Sixth Circuit, petitioners argued that the District Court’s conclusion must be read, in light of its findings, as holding that double celling is per se unconstitutional. The Court of Appeals disagreed; it viewed the District Court’s opinion as holding only that double celling is cruel and unusual punishment under the circumstances at SOCF. It affirmed, without further opinion, on the ground that the District Court’s findings were not clearly erroneous, its conclusions of law were “permissible from the findings,” and its remedy was a reasonable response to the violations found.10
We granted the petition for certiorari because of the importance of the question to prison administration. 449 U. S. 951 (1980). We now reverse.
II
We consider here for the first time the limitation that the Eighth Amendment, which is applicable to the States through *345the Fourteenth Amendment, Robinson v. California, 370 U. S. 660 (1962), imposes upon the conditions in which a State may confine those convicted of crimes. It is unquestioned that “[c]onfinement in a prison ... is a form of punishment subject to scrutiny under the Eighth Amendment standards.” Hutto v. Finney, 437 U. S. 678, 685 (1978); see Ingraham v. Wright, 430 U. S. 651, 669 (1977); cf. Bell v. Wolfish, 441 U. S. 520 (1979). But until this case, we have not considered a disputed contention that the conditions of confinement at a particular prison constituted cruel and unusual punishment.11 Nor have we had an occasion to consider specifically the principles relevant to assessing claims that conditions of confinement violate the Eighth Amendment. We look, first, to the Eighth Amendment precedents for the general principles that are relevant to a State’s authority to impose punishment for criminal conduct.
A
The Eighth Amendment, in only three words, imposes the constitutional limitation upon punishments: they cannot be “cruel and unusual.” The Court has interpreted these words “in a flexible and dynamic manner,” Gregg v. Georgia, 428 U. S. 153, 171 (1976) (joint opinion), and has extended the Amendment’s reach beyond the barbarous physical punishments at issue in the Court’s earliest cases. See Wilkerson *346v. Utah, 99 U. S. 130 (1879); In re Kemmler, 136 U. S. 436 (1890). Today the Eighth Amendment prohibits punishments which, although not physically barbarous, “involve the unnecessary and wanton infliction of pain,” Gregg v. Georgia, supra, at 173, or are grossly disproportionate to the severity of the crime, Coker v. Georgia, 433 U. S. 584, 592 (1977) (plurality opinion); Weems v. United States, 217 U. S. 349 (1910).12 Among “unnecessary and wanton” inflictions of pain are those that are “totally without penological justification.” Gregg v. Georgia, supra, at 183; Estelle v. Gamble, 429 U. S. 97, 103 (1976).
No static “test” can exist by which courts determine whether conditions of confinement are cruel and unusual, for the Eighth Amendment “must draw its meaning from the evolving standards of decency that mark the progress of a maturing society.” Trop v. Dulles, 356 U. S. 86, 101 (1958) (plurality opinion). The Court has held, however, that “Eighth Amendment judgments should neither be nor appear to be merely the subjective views” of judges. Rummel v. Estelle, 445 U. S. 263, 275 (1980). To be sure, “the Constitution contemplates that in the end [a court’s] own judgment will be brought to bear on the question of the acceptability” of a given punishment. Coker v. Georgia, supra, at 597 (plurality opinion); Gregg v. Georgia, supra, at 182 (joint opinion). But such “ ‘judgment[s] should be informed by objective factors to the maximum possible extent.’ ” Rummel v. Estelle, supra, at 27A-275, quoting Coker v. Georgia, supra, at 592 (plurality opinion). Eor example, when the question was whether capital punishment for certain crimes violated contemporary values, the Court looked for “objective indicia” derived from history, the action of *347state legislatures, and the sentencing by juries. Gregg v. Georgia, supra, at 176-187; Coker v. Georgia, supra, at 593-596. Our conclusion in Estelle v. Gamble, supra, that deliberate indifference to an inmate’s medical needs is cruel and unusual punishment rested on the fact, recognized by the common law and state legislatures, that “[a]n inmate must rely on prison authorities to treat his medical needs; if the authorities fail to do so, those needs will not be met.” 429 U. S., at 103.
These principles apply when the conditions of confinement compose the punishment at issue. Conditions must not involve the wanton and unnecessary infliction of pain, nor may they be grossly disproportionate to the severity of the crime warranting imprisonment. In Estelle v. Gamble, supra, we held that the denial of medical care is cruel and unusual because, in the worst case, it can result in physical torture, and, even in less serious cases, it can result in pain without any penological purpose. 429 U. S., at 103. In Hutto v. Finney, supra, the conditions of confinement in two Arkansas prisons constituted cruel and unusual punishment because they resulted in unquestioned and serious deprivations of basic human needs. Conditions other than those in Gamble and Hutto, alone or in combination, may deprive inmates of the minimal civilized measure of life’s necessities. Such conditions could be cruel and unusual under the contemporary standard of decency that we recognized in Gamble, supra, at 103-104. But conditions that cannot be said to be cruel and unusual under contemporary standards are not unconstitutional. To the extent that such conditions are restrictive and even harsh, they are part of the penalty that criminal offenders pay for their offenses against society.
B
In view of the District Court’s findings of fact, its conclusion that double celling at SOCF constitutes cruel and unusual punishment is insupportable. Virtually every one *348of the court’s findings tends to refute respondents’ claim. The double celling made necessary by the unanticipated increase in prison population did not lead to deprivations of essential food, medical care, or sanitation. Nor did it increase violence among inmates or create other conditions intolerable for prison confinement. 434 F. Supp., at 1018. Although job and educational opportunities diminished marginally as a result of double celling, limited work hours and delay before receiving education do not inflict pain, much less unnecessary and wanton pain; deprivations of this kind simply are not punishments. We would have to wrench the Eighth Amendment from its language and history to hold that delay of these desirable aids to rehabilitation violates the Constitution.
The five considerations on which the District Court relied also are insufficient to support its constitutional conclusion. The court relied on the long terms of imprisonment served by inmates at SOCF; the fact that SOCF housed 38% more inmates than its “design capacity”; the recommendation of several studies that each inmate have at least 50-55 square feet of living quarters; the suggestion that double-celled inmates spend most of their time in their cells with their cellmates; and the fact that double celling at SOCF was not a temporary condition. Supra, at 343-344. These general considerations fall far short in themselves of proving cruel and unusual punishment, for there is no evidence that double celling under these circumstances either inflicts unnecessary or wanton pain or is grossly disproportionate to the severity of crimes warranting imprisonment.13 At most, these con*349siderations amount to a theory that double celling inflicts pain.14 Perhaps they reflect an aspiration toward an ideal environment for long-term confinement. But the Constitution does not mandate comfortable prisons, and prisons of SOCF’s type, which house persons convicted of serious crimes, cannot be free of discomfort. Thus, these considerations properly are weighed by the legislature and prison administration rather than a court. There being no constitutional violation,15 the District Court had no authority to con*350sider whether double celling in light of these considerations was the best response to the increase in Ohio’s statewide prison population.
*351III
This Court must proceed cautiously in making an Eighth Amendment judgment because, unless we reverse it, “[a] decision that a given punishment is impermissible under the Eighth Amendment cannot be reversed short of a constitutional amendment,” and thus “[revisions cannot be made in the light of further experience.” Gregg v. Georgia, 428 U. S., at 176. In assessing claims that conditions of confinement are cruel and unusual, courts must bear in mind that their inquiries “spring from constitutional requirements and that judicial answers to them must reflect that fact rather than a court’s idea of how best to operate a detention facility.” Bell v. Wolfish, 441 U. S., at 539.16
*352Courts certainly have a responsibility to scrutinize claims of cruel and unusual confinement, and conditions in a number of prisons, especially older ones, have justly been described as “deplorable” and “sordid.” Bell v. Wolfish, supra, at 562.17 When conditions of confinement amount to cruel and unusual punishment, “federal courts will discharge their duty to protect constitutional rights.” Procunier v. Martinez, 416 U. S. 396, 405-406 (1974); see Cruz v. Beto, 405 U. S. 319, 321 (1972) (per curiam). In discharging this oversight responsibility, however, courts cannot assume that state legislatures and prison officials are insensitive to the requirements of the Constitution or to the perplexing sociological problems of how best to achieve the goals of the penal function in the criminal justice system: to punish justly, to deter future crime, and to return imprisoned persons to society with an improved chance of being useful, law-abiding citizens.
In this case, the question before us is whether the conditions of confinement at SOCF are cruel and unusual. As we find that they are not, the judgment of the Court of Appeals is reversed.
It is so ordered.
As a result of the judgment in respondents’ favor, double celling has been substantially eliminated at SOCF. But the increases in Ohio’s statewide prison population, which prompted double celling at SOCF, have continued. Furthermore, because SOCF is Ohio’s only maximum-security prison, the transfer of some of SOCF’s inmates into lesser security prisons has created special problems for the recipient prisons. Tr. of Oral Arg. 5-6. Thus, petitioners have an interest in resuming double celling at SOCF. See Bell v. Wolfish, 441 U. S. 520, 542-543, n. 25 (1979).
SOCF’s library contains 25,000 volumes, including lawbooks, and was described by the District Court as “modern, well-lit,” and “superior in quality and quantity.” 434 F. Supp., at 1010. The court described SOCF’s classrooms as “light, airy, and well equipped.” Id., at 1015. The court did not describe SOCF’s workshops except to identify them as a laundry, machine shop, shoe factory, sheet metal shop, printshop, sign shop, and engine-repair shop. See id., at 1010.
Inmates who requested protective custody but could not substantiate their fears were classified as “limited activity” and were locked in their cells all but six hours a week. Inmates classified as “voluntarily idle” and newly arrived inmates awaiting classification had only four hours a week outside their cells. Inmates housed in administrative isolation for disciplinary reasons were allowed out of their cells for two hours a week to attend religious services, a movie, or the commissary.
The court noted that SOCF is one of the few maximum-security prisons in the country to permit contact visitation for all inmates. Id., at 1014.
The court found that adequate lawbooks were available, even to inmates in protective or disciplinary confinement, to allow effective access to court. As to school, no inmate who was “ready, able, and willing to receive schooling has been denied the opportunity,” although there was some delay before an inmate received the opportunity to attend. Id., at 1015.
Turnover in the dental staff had caused a temporary but substantial backlog of inmates needing routine dental care, but the dental staff treated emergencies. Id., at 1016.
The District Court cited, e. g., American Correctional Assn., Manual of Standards for Adult Correctional Institutions, Standard No. 4142, p. 27 (1977) (60-80 square feet); National Sheriffs’ Assn., A Handbook on Jail Architecture 63 (1975) (70-80 square feet); National Council on Crime and Delinquency, Model Act for the Protection of Rights of Prisoners, § 1, 18 Crime & Delinquency 4, 10 (1972) (50 square feet).
The basis of the District Court’s assertion as to the amount of time that inmates spend in their cells does not appear in the court’s opinion. Elsewhere in its opinion, the court found that 75% of the double-celled inmates at SOCF are free to be out of their cells from 6:30 a. m. to 9 p. m. 434 F. Supp., at 1012, 1013. The court stated that it made this finding on the basis of prison regulations on inmate classification, which petitioners submitted as exhibits. Id., at 1012.
Rather than order that petitioners either move respondents into single cells or release them, as respondents urged, the District Court initially ordered petitioners to “proceed with reasonable dispatch to formulate, propose, and carry out some plan which will terminate double celling at SOCF.” Id., at 1022. Petitioners submitted five plans, each of which the court rejected. It then ordered petitioners to reduce the inmate population at SOCF by 25 men per month until the population fell to the prison’s approximate design capacity of 1,700. App. to Pet. for Cert. A-39.
The Court of Appeals stated its conclusion in a two-paragraph order of affirmance that it filed but did not publish. See 624 F. 2d 1099 (1980).
In Hutto v. Finney, 437 U. S. 678 (1978), the state prison administrators did not dispute the District Court’s conclusion that the conditions in two Arkansas prisons constituted cruel and unusual punishment. Id., at 685. In Ingraham v. Wright, 430 U. S. 651 (1977), the question was whether corporal punishment in a public school constituted cruel and unusual punishment. We held that the Eighth and Fourteenth Amendments do not apply to public school disciplinary practices. In considering the differences between a prisoner and a schoolchild, we stated: “Prison brutality ... is ‘part of the total punishment to which the individual is being subjected for his crime and, as such, is a proper subject for Eighth Amendment scrutiny.’” Id., at 669, quoting Ingraham v. Wright, 525 F. 2d 909, 915 (CA5 1976).
The Eighth Amendment also imposes a substantive limit on what can be made criminal and punished as such. Robinson v. California, 370 U. S. 660 (1962). This aspect of the Eighth Amendment is not involved in this case.
Respondents and the District Court erred in assuming that opinions of experts as to desirable prison conditions suffice to establish contemporary standards of decency. As we noted in Bell v. Wolfish, 441 U. S., at 543-544, n. 27, such opinions may be helpful and relevant with respect to some questions, but “they simply do not establish the constitutional minima; rather, they establish goals recommended by the organization in question.” See U. S. Dept. of Justice, Federal Standards for Prisons and Jails 1 (1980). Indeed, generalized opinions of experts cannot weigh as *349heavily in determining contemporary standards of decency as “the public attitude toward a given sanction.” Gregg v. Georgia, 428 U. S. 153, 173 (1976) (joint opinion). We could agree that double celling is not desirable, especially in view of the size of these cells. But there is no evidence in this ease that double celling is viewed generally as violating decency. Moreover, though small, the cells in SOCF are exceptionally modern and functional; they are heated and ventilated and have hot and cold running water and a sanitary toilet. Each cell also has a radio. 434 F. Supp., at 1011.
Respondents contend that the close confinement of double celling for long periods creates a dangerous potential for frustration, tension, and violence. In respondents’ view, it would be an infliction of unnecessary and wanton pain if double celling led to rioting. The danger of prison riots is a serious concern, shared by the public as well as by prison authorities and inmates. But respondents’ contention does not lead to the conclusion that double celling at SOCF is cruel and unusual, whatever may be the situation in a different case. The District Court’s findings of fact lend no support to respondents’ claim in this case. Moreover, a prison’s internal security is peculiarly a matter normally left to the discretion of prison administrators. See Bell v. Wolfish, supra, at 551, and n. 32; Jones v. North Carolina Prisoners’ Labor Union, 433 U. S. 119, 132-133 (1977); Pell v. Procunier, 417 U. S. 817, 827 (1974).
The dissenting opinion states that “the facility described by [the Court] is not the one involved in this case.” Post, at 369-370. The incorrectness of this statement is apparent from an examination of the facts set forth at length above, see supra, at 340-343, and nn. 2-6, and the District Court’s detailed findings of fact. See 434 F. Supp., at 1009-1018.
In several instances, the dissent selectively relies on testimony without acknowledging that the District Court gave it little or no weight. For example, the dissent emphasizes the testimony of experts as to psychological problems that “may be expected” from double celling; it also *350relies on similar testimony as to an increase in tension and aggression. Id., at 1017. The dissent fails to mention, however, that the District Court also referred to the testimony by the prison superintendent and physician that “there has been no increase [in violence] other than what one would expect from increased numbers [of inmates].” Id., at 1018. More telling is the fact — ignored by the dissent — that the District Court resolved this conflict in the testimony by holding “that there had been no increase in violence or criminal activity increase due to double celling; there has been [an increase] due to increased population.” Ibid. This holding was based on uncontroverted prison records, required to be maintained by the Ohio Department of Corrections and described by the District Court as being “detailed] and bespeak[ing] credibility.” Ibid.
There is some ambiguity in the opinion of the District Court concerning the amount of time that double-celled inmates were required to remain in their cells. The dissent, post, at 373, n. 6, relies only on selective findings that most inmates are out of their cells only 10 hours each day, and that others are out only 4^6 hours a week. 434 F. Supp., at 1013. The dissent fails to note that the first of these findings is flatly inconsistent with a prior, twice-repeated, finding by the court that inmates “have to be locked in their cell with their cellmate only from around 9:00 p. m. to 6:30 a. m.,” id., at 1013, 1012, leaving them free to move about for some 14 hours. Moreover, it is unquestioned — and also not mentioned by the dissent — that the inmates who spend most of their time locked in their cells are those who have a “restrictive classification.” These include inmates found guilty of “rule infractions [after] a plenary hearing” and inmates who “are there by 'choice’ (at least to some degree).” Ibid. It must be remembered that SOCF is a maximum-security prison, housing only persons guilty of violent and other serious crimes. It is essential to maintain a regime of close supervision and discipline.
The dissent also makes much of the fact that SOCF was housing 38% more inmates at the time of trial than its “rated capacity.” According to the United States Bureau of Prisons, at least three factors influence prison population: the number of arrests, prosecution policies, and sentencing and parole decisions. Because these factors can change rapidly, while prisons require years to plan and build, it is extremely difficult to calibrate a prison’s “rated” or “design capacity” with predictions of prison population. Memorandum of United States as Amicus Curiae 3, 6. The question before us is not whether the designer of SOCF guessed incor*351rectly about future prison population, but whether the actual conditions of confinement at SOCF are cruel and unusual.
We have sketched before the magnitude of the problems of prison administration. Procunier v. Martinez, 416 U. S. 396, 404-405 (1974). See generally National Institute of Justice, American Prisons and Jails (1980) (5 vols.). It suffices here to repeat:
“[T]he problems of prisons in America are complex and intractable, and, more to the point, they are not readily susceptible of resolution by decree. Most require expertise, comprehensive planning, and the commitment of resources, all of which are peculiarly within the province of the legislative and executive branches of government. For all of those reasons, courts are ill equipped to deal with the increasingly urgent problems of prison administration and reform. Judicial recognition of that fact reflects no more than a healthy sense of realism.” Procunier v. Martinez, supra, at 404-405 (footnote omitted).
See also Wolff v. McDonnell, 418 U. S. 539, 561-562, 568 (1974); Jones v. North Carolina Prisoners’ Labor Union, supra, at 125.
Since our decision in Martinez, the problems of prison population and administration have been exacerbated by the increase of serious crime and the effect of inflation on the resources of States and communities. This case is illustrative. Ohio designed and built SOCF in the early 1970’s, and even at the time of trial it was found to be a modern “topflight, first-class facility.” Supra, at 341. Yet, an unanticipated increase in the State’s prison population compelled the double celling that is at issue.
Examples of recent federal-court decisions holding prison conditions to be violative of the Eighth and Fourteenth Amendments include Ramos v. Lamm, 639 F. 2d 559 (CA10 1980), cert. denied, 450 U. S. 1041 (1981); Williams v. Edwards, 547 F. 2d 1206 (CA5 1977); Gates v. Collier, 501 F. 2d 1291 (CA5 1974); Pugh v. Locke, 406 F. Supp. 318 (MD Ala. 1976), aff'd as modified, 559 F. 2d 283 (CA5 1977), rev’d in part on other grounds, 438 U. S. 781 (1978) (per curiam).