Skip to main content

Quṭb Al-D


(b. Shiraz, Persia Safar 1236; d. Tabriz, Persia, 17 Ramadan 1311)

optics, astronomy, medicine, philosophy.

Quṭb al-Dīn Mahmud was born into a well-known family of physicians and Sufis. His father, Dia al-Dīn Masud, was both a Sufi master attached to Shihab al-Dīn al-Suhrawardi and a famous physician; and under his guidance Quṭb al-Dīn received his early training in both medicine and Sufism. At the time of his father’s death Quṭb al-Dīn was but fourteen years old, yet he was entrusted with his father’s duties as physician and ophthalmologist at the Muzaffari hospital in Shiraz, where he remained for ten years.

At the age of twenty-four his love of learning led Quṭb al-Dīn to leave his position at the hospital in order to devote himself fully to his studies, especially in medicine. He studied lbn Sīnā’s Canon with several of the best-known masters of his day, but he could not find a teacher who satisfied him completely. He therefore traveled from city to city, seeking masters who could instruct him in both the medicine and the philosophy of lbn Sīnā, a figure who attracted him greatly. In his journeys Quṭb al-Dīn met many Sufi masters, whose gatherings he frequented. He traveled in Khurasan, Iraq, and Anatolia, meeting most of the medical authorities of the day. Also during these journeys he was initiated formally into Sufism at the age of thirty by Muhyi’l-Din Abmad ibn ’A1i, a disciple of Najm al-Dīn Kubra.

Around 1262 Quṭb al-Dīn became associated with his most famous teacher, Naṣīr al-Dīn al-Tūsī, at Marāgha; his superior intelligence soon made him al-Tūsī’s foremost student. With al-Tūsī he studied both astronomy and the philosophy of lbn Sīnā, particularly al-Isharal wa’l-tanbihat (“Book of Directives and Remarks”). After a long period during which he was closely connected with the circle of Naṣīr al-Dīn, Quṭb al-Dīn left Marāgha for Khurasan to study with another well-known philosopher, Najm al-Dīn Dabiran Katibi al-Qazwini. His studies later took him to Qazvin and Baghdad, where he stayed at the Nizamiyya school. From there he set out for Konya and became a follower of the celebrated Sufi and disciple of Ibn ’Arabi, Sadr al-Dīn al-Qunyawi, with whom he studied the religious sciences such as Quranic commentary and Hadith. After the death of Sadr al-Dīn, Quṭb al-Dīn left Konya to become judge in Sivas and Molatya, starting the period during which some of his major works appeared.

When he later moved to Tabriz, Quṭb al-Dīn attracted the attention of the son of Hulagu Khan, Ahmad Takudar, who was then ruling Persia. The latter sent him as ambassador to the court of the Mameluke ruler of Egypt, Sayf al-Dīn Qala’un. This journey was of major scientific importance for him, for during this period he gained access to some of the important commentaries upon Ibn Sīnā’s Canon, which he had long sought and which were to serve him in the preparation of his major commentary upon this work. In 1283 he finally began to write this commentary, which occupied him for most of the rest of his life.

From Egypt, Quṭb al-Dīn returned to Tabriz, where he met the important scholarly figures of his day, such as the learned vizier and historian Rashid al-Dīn Fadlallah. It was in this capital of the II-Khanids that he died, after nearly fourteen years spent mostly in seclusion and devoted to writing. His love of learning became proverbial in Persia; he was given the honorific title ’Allama, rare in medieval times, and the historian Abu’l-Fida gave him the title al-Muta-fannin, “master in many sciences.” lie was also called “the scholar of the Persians.” lie was known as a master chess player and an excellent player of the lute, and he spent much of his time on these two pastimes.

Although Quṭb al-Dīn was among the foremost thinkers and scholars of Islam. only two of his works have been printed: the Durrat al-taj and the Sharh Hikmat al-ishrāq, the latter only in a lithographed edition. The rest of his writings remain in manuscript. The entire body of his thought cannot be known until these works are edited and made accessible for study.

Quṭb al-Dīn’s geometrical works are the following:

1. The Persian translation of Naṣīr al-Dīn al-Ṭūsi’s Tahrir Usul Uqilidus (“Recension of the Elements of Euclid”).

2. Risāla fi harakat al-dahraja wa’l-nisba bayn al-mustawi wa’l-munhani (“Treatise on the Motion of Rolling and the Relation Between the Straight and the Curved”).1

Those on astronomy and geography are the following:

3. Nihāyat al-idrak fi dirāyat al-aflāk (“The Limit of Understanding of the Knowledge of the Heavens”). Quṭb al-Dīn’s major astronomical work, it consists of four books: introduction, the heavens, the earth, and the “quantity” of the heavens. There are sections on cosmography, geography, geodesy, meteorology, mechanics, and optics, reflecting both the older scientific views of lbn al-Haytham and al-Bīrūnī and new scientific theories in optics and planetary motion. This work was completed around 1281 and has been commented upon by Sinān Pāshā.

4.lkhtiyārāt-i muzaffari (“Muzaffari Selections”). This work, one of Quṭb al-Dīn’s masterpieces, contains his own views on astronomy and is perhaps the best work on astronomy in Persian. It is a synopsis of the Nihāya; is composed, like that work, of four sections; and was written sometime before 1304. Tuhfat al-shāhiyya fi’1-hay’a (“The Royal Gift on Astronomy” Composed shortly after the Nihāya (in 1284), to solve more completely problems begun in the earlier work, it constitutes, along with the Nihāya Quṭb al-Dīn’s masterpiece in mathematical astronomy. About these two works Wiedemann wrote, “Kutb al-Dīn has in my opinion given the best Arabic account of astronomy (cosmography) with mathematical aids.”2 This work, like the Nihāya, was celebrated in later Islamic history and has been commented upon by Sayyid Sharif and ’Ali Qūshchi.

6. Kitāb fa’altu fa-lā talum fi’l-hay’a (“A Book I Have Composed, But Do Not Blame [Me for It], on Astronomy”).

7. Kitāb al-tabsira fi’l-hay’a (“The Tabsira on Astronomy”).

8. Sharh al-tadhkira al-Naṣīriyya (“Commentary Upon the Tadhkira of Naṣīr al-Dīn”). Commentary upon the famous Tadhkira of Naṣīr al-Dīn al-Tūsī and also on the Bayān maqāsid al-tadhkira of Muhammad ibn ‘Ali al-Himādhī.

9.Kharīdat ai-ajā ib (“The Wonderful Pearl”).

10.Khulāṣat Istāh al-majisti li-Jabir ibn Aflalh (“Extracts of Correction of the Almagest of Jabir ibn Aflah”).

11.Hall mushkilāt al-majisti (“Solution of the Difficulties of the Almagest”). A work that is apparently lost.

12. Tahrīr al-zij al-jadīd al-ridwānī (“Recension of the New Ridwānī Astronomical Tables”).

13. al-Zīj al-sultānī (“The Sultani Astronomical Tables”). These tables have been attributed to both Quṭb al-Dīn and Muhammad ibn Mubarak Shams al-Dīn Mirak al-Bukhārī.

Medical works by Quṭb al-Dīn include the following:

14.Kitāb nuzhat al-hukamā wa rawdat al-atibba (“Delight of the Wise and Garden of the Physicians”), also known as al-Tuhfat al-sadiyya (“The Presentation to Sad”) and Sharh kulliyyat al-qanum (“Commentary Upon the Principles of the Canon of Ibn Slna”). This is the largest work by Quṭb al-Dīn, in five volumes. He worked on it throughout his life and dedicated it to Muhammad Sad al-Dīn, the vizier of Arghūn and the il-Khanid ruler of Persia.

15. Risāla f1 l-baras (“Treatise on Leprosy”).

16. Sharh al-Urjūza (“Commentary Upon Ibn Sīnā’s Canticum”).

17. Risāla fī bayān al-hāja ila’l-tibb wa-ādab al-atibbā wa-waṣāyāhum(“Treatise on the Explanation of the Necessity of Medicine and of the Manners and Duties of Physicians”).

Theosophical, philosophical, and encyclopedic works are the following;

18. Durrat al-tāj li ghurrat al-dībāj fil-hikma (“Pearls of the Crown, the Best Introduction to Wisdom”). This encyclopedic philosophical and scientific work in Persian comprises an introduction on knowledge and the classification of the sciences; five books (jumla) dealing with logic, metaphysics, natural philosophy, mathematics, and theodicy; and a four-part conclusion on religion and mysticism. The introduction, and the books on logic, metaphysics, and theodicy, were published by S. M. Mishkat (Teheran, 1938–1941), and book 4 on mathematics, excluding certain portions on geometry, by S. H. Tabasi (Teheran, 1938–1944).

The philosophical sections of Durrat al-tāj were greatly influenced by the writings of Ibn Sīnā and Suhrawardi; the geometry is mostly a Persian translation of Euclid”s Elements with the paraphrases and commentaries of al-Hajjaj and Thabit ibn Qurra. The astronomy is a translation of the Summary of the Almagest of Abd al-Malik ibn Muhammad al-Shirāzī, and the music is taken from al-Farabi, Ibn Sīnā, and Abd al-Mu min. In the sections on religion and ethics, Quṭb al-Dīn made use of the writings of Ibn Sīnā and Fakhr al-Dīn al-rāzī; and in Sufism or mysticism, of the Manahij al-ibdd ila l-ma ad of Sad al-Dīn al-Farghani, a disciple of Mawlana Jala al-Dīn Rumi and Sadr al-Dīn al-Qunyawi.

19. Sharh Hikmat al-ishrāq (“Commentary Upon the Theosophy of the Orient of Light”). The best-known commentary upon Suhrawardī’s Hikmat al-ishrāq, it was published in a lithographed edition (Teheran, 1897).

20. Sharh Kitāb rawdat al-nāzir (“Commentary Upon the Rawdat al-nāzir”). A commentary upon Naṣīr al-Dīn al-Ṭūsī’s Rawdat al-nazir on questions of ontology.

21. Sharh al-najāt (“Commentary Upon the Najāt”). Commentary upon Ibn Sinā’s Kitāb al-najāt. wa’l-hashiya ala l-Isharat wa l-tanbihat (“Commentary and Glosses Upon the Isharat”). Commentary upon Ibn Sīnā’s last philosophical masterpiece, the Isharat.

23. Hdshiya ala Hikmat al-ayn (“Glosses Upon the Hikmat al-ayn”). The first commentary upon Najm al-Dīn Dabiran al-Katibi s well-known Hikmat al-ayn, upon which many commentaries appeared later.

24. Unmūzaj al-ulūm (“A Compendium of the Sciences”).

25. Wajiza fi l-tasawwur wa l-tasdiq (“A Short Treatise on Concept and Judgment”).

26. Risāla dar ilm-i akhlāq (“Treatise on Ethics”)A treatise in Persian which is apparently lost.

The rest of the works by Quṭb al-Dīn treat the sciences of language and strictly religious questions, and there is no need to deal with them here. He also left a few poems of some literary quality.

Philosophy and Theology . Quṭb al-Dīn belonged to that group of Muslim philosophers between Suhrawardi and Mulla Sadra who revived the philosophy of Ibn Sīnā after the attacks of al-Ghazali, giving it at the same time an illuminationist quality drawn from the teaching of Suhrawardi. After his teacher Naṣīr al-Dīn al-Tūsī, Quṭb al-Dīn must be considered the foremost philosophical figure during the four centuries which separated Suhrawardi from Mulla Sadra. Quṭb al-Dīn was also a leading example of the Muslim sage or hakim who was the master of many disciplines and wrote definitive works in each of them. His Durrat al-taj is the outstanding Persian encyclopedia of Peripatetic philosophy. Written on the model of Ibn Sīnā’s al-Shifā it has additional sections devoted to Ṣūfism and strictly religious matters not found in earlier Peripatetic works. His commentary upon the Hikmat aNshraq, although based mostly upon that of Shahrāzīiri, rapidly replaced the latter as the most famous such work. Later generations saw Suhrawardi mostly through the eyes of Quṭb al-Dīn. His theological and religious writings also commanded great respect. The thirteenth and fourteenth centuries were marked in Persia by the gradual rapprochement of the four intellectual schools of theology (kalam). Peripatetic philosophy (mashsha) illuminationist theosophy (ishrāq), and gnosis (irfan). Quṭb al-Dīn was one of the key figures who brought this about and prepared the way for the synthesis of the Safavid period. He was at once a fervent disciple of Ibn Slna, the master of Peripatetics; a commentator on Suhrawardi, the founder of the ishrāqi school; and a student of Sadr al-Dīn al-Qunyawi, the closest disciple of the greatest expositor of the gnostic teachings of Islam, Ibn Arabl. Furthermore he was a theologian and religious scholar of note. To all of these he added his remarkable acumen in mathematics, astronomy, physics, and medicine, for which he has become known as much as a scientist as a philosopher.

Mathematics . Quṭb al-Dīn attached a metaphysical significance to the study of mathematics, which he viewed more in the Pythagorean than in the Aristotelian manner. He saw it as the means to discipline the soul for the study of metaphysics and theosophy. His greatest contributions came in astronomy and optics, which were then part of the mathematical sciences, rather than in pure mathematics in the modern sense.

Optics . After Ibn al-Haytham there was a relative lack of interest in optics among Muslims; the optical writings even of Naṣīr al-Dīn al-Tūsī show a definite decline in comparison. Probably mostly because of the spread of Suhrawardi’s newly founded school of illumination, which made light synonymous with being and the basis of all reality, a definite renewal of interest in optics occurred in the thirteenth century, for which Quṭb al-Dīn was largely responsible. Although he did not write separate treatises on optics, his Nihāyat al-idrak contains sections devoted to the subject. He was especially interested in the phenomena of the rainbow and must be considered the first to have explained it correctly. He concluded that the rainbow was the result of the passage of light through a transparent sphere (the raindrop). The ray of light is refracted twice and reflected once to cause the observable colors of the primary bow. The special attention paid by Quṭb al-Dīn and his students was in fact responsible for the creation in Islam of a separate science of the rainbow (qaws qazalt), which first appeared in the classification of the sciences at this time. The significance of Quṭb al-Dīn in optics also lies in his transmission of the optical teachings of Ibn al-Haytham to al-Fārisī, who then composed the most important commentary upon Ibn al-Haytham’s Optics, the Tanqih al-Matiazir.

Also of interest in this field is Quṭb al-Dīn’s theory of vision in his Sharh Hikmat alishrāq, in which he rejected both the Euclidean and the Aristotelian theories and confirmed the ishrāqi theory, according to which vision occurs when there is no obstacle between the eye and the object. When the obstacle is removed, the soul of the observer receives an illumination through which the whole of the object is perceived as a single reality.

Astronomy . Quṭb al-Dīn wrote at the beginning of his lkhtiyardt that the principles of astronomy fall under three headings: religion, natural philosophy, and geometry. Those who study this science become dear to God, and the student of astronomy becomes prepared for the understanding of the divine sciences because his mind is trained to study immaterial objects. Moreover, through the study of astronomy the soul gains such virtues as perseverance and temperance, and aspires to resemble the heavenly spheres. He definitely believed that the study of astronomy possessed a religious value and he himself studied it religiously and with reverence.

Quṭb al-Dīn played a major role in the observations made at Marāgha which led to the composition of the Ilkhani zlj although his name is not mentioned in its introduction. In his Nihāya he suggested that the values listed in the Ilkhani zij for the motion of the apogee were not based on calculation from the successive equinoxes but were dependent upon repeated observations. He asserted that the shift in the solar apogee could be confirmed by comparing the values found in Ptolemy and the later astronomical tables preceding the Ilkhani zij which implies recourse to frequent observations. Quṭb al-Dīn was keenly interested in scientific observation, but this in no way reduced his viewpoint to empiricism or detracted from his theoretical interests or philosophical vision.

Quṭb al-Dīn emphasized the relation between the movement of the sun and the planets in the way that is found later in the writings of Regiomontanus, and which prepared the way for Copernicus. In fact, through the research of E. S. Kennedy and his associates, it has been discovered that new planetary models came out of Marāgha which represent the most important departure from the Ptolemaic model in medieval times and are essentially the same as those of Copernicus, provided one ignores the heliostatic hypothesis.

The Marāgha school sought to remove a basic flaw from the Ptolemaic model for planetary motion, namely, the failure of certain Ptolemaic configurations to conform to the principle that essential motion must be uniform and circular. To remedy this situation Naṣīr al-Dīn al-Tūsī proposed in his Tadhkira a rolling device consisting of two vectors (to use the modern terminology) of equal length, the second moving with a constant velocity twice that of the first but in the opposite direction. This device Kennedy has named the “Tūsī couple.”

Quṭb al-Dīn in his Nihāya and al-Tuhfat al-shāhiyya, both of which, like the Tadhkira,are divided into four parts, sought to work out this model for the different planets but apparently never did so to his full satisfaction, for he kept modifying it. In fact, he produced the two above-mentioned works within four years, in an attempt to achieve the final answer. In the several manuscripts of each, the two works contain successive endeavors to reach a completely satisfactory solution to what is definitely Quṭb al-Dīn’s most important achievement in astronomy.

The planetary model which Quṭb al-Dīn used for all the planets except Mercury can be summarized as shown below (see Figure 1).3

As the figure shows, a vector of length 60 which is in the direction of the mean longitude is drawn from a point midway between the equant center and the deferent center. Another vector, with a length equal to half the eccentricity, rotates at the end of this vector.

Because of the great eccentricity of Mercury, its model requires special conditions. Figure 2 demonstrates how Quṭb al-Dīn was finally able to create a model which fulfilled the conditions for this planet.

As E. S. Kennedy—to whom we owe this analysis and figure—states:

The first vector r1 is of length 60, it issues from the deferent center, and it has at all times the direction of the mean planet. The next four vectors, each of length c/2 [where because the eccentricity of Mercury is 6], make up two Tūsī couples. The last vector has length. The initial positions and rates of rotation of all the vectors are as shown on the drawing,where is the mean longitude measured from apogee.4

This model represents the height of the techniques developed at Marāgha to solve the problems of planetary moon. Quṭb al-Dīn also applied these techniques to the solution of the problem moon, trying to remove some of the obvious flaws in the Ptolemaic model. But in this matter another Muslim astronomer who adopted these techniques, Ibn al-Shāṭir, was more successful. He produced a model that was greatly superior to that of Ptolemy, the same that was produced later by Copernicus.

Geógraphy . The interest of Quṭb al-Dīn in observation is also evident in geography. Not only did he write on geography in his Nihāyadrawing from earlier Muslim geographers, especially al-Bīrūnī, but he traveled thought out Asia Minor, examining the route to be followed by the Genoese ambassador of the Mongol ruler Arghūn to the Pope, Buscarello di Ghizalfi. In 1290 he presented a map of the Mediterranean to Arghūn based on observations made of the coastal areas Asia Minor.

Physics . In his Peripatetic works Quṭb al-Dīn generally followed the physics of Ibn Sīnā, but in the Sharh Hikmat al-ishrāq he developed a physics of light which is of particular interest. In it he considered light as the source of all motion, both sublunar and celestial. In the case of the heavenly spheres, motion is a result of the illumination of the souls of the spheres by divine light. He divided bodies into simple and compound, and these in turn into transparent and opaque, so that light and darkness, rather than the Aristotelian hylomorphism, dominate his physics. He also reinterpreted meteorological phenomena in terms of light and light phenomena.

Medicine . Quṭb al-Dīn’s major contribution to medicine was his commentary upon Ibn Sīnā’s Canon, which was celebrated in later centuries in the Islamic world but has not been analyzed thoroughly in modern times. This seeks to explain all the difficulties in the Cannonrelating to general principles of medicine. Quṭb al-Dīn based it not only on his own life long study of the text and what he had learned from his masters in Shiraz, Marāgha, and other cities, but also on all the important commentaries he found in Egypt, especially the Mujiz al-Qanumof Ibn al-Nafis, the Sharh al-Kulliyyat min kitāb al-Qanumof Muwaffaq al-Dīn Yaqub al-Smarri, and the Kitab al-Shaft fi’l-tibb of Abu’l-Faraj ibn al-Quff. In medicine, as in philosophy, Quṭb al-Dīn did much to revive the teachings of Ibn Sīnā and had an important role in the propagation of Avicennan medicine, especially from the fifteenth century onward in the Indian subcontinent.

Influence . The most famous students of Quṭb al-Dīn were al-Fārisī, the outstanding commentator on Ibn al-Haytham; Quṭb al-Dīn al-rāzī, the author of many famous works, including the Muḥākamāt,a “trial” of the relative merits of the commentaries of Naṣīr al-Dīn al-Tūsī and Fakhr al-Dīn al-rāzī upon the Isharat of Ibn Sīnā; and Nizam al-Dīn al-Naishapuri the author of Tafsir al-Tahrir, on Naṣīr al-Dīn al-Tūsī’s Recension of the Almagest. Quṭb al-Dīn’s influence continued through these and other students,

and also through his writings, especially the al-Tuhfat al-sa’diyya in medicine, Nihāyat al-idrāk in astron- omy, and Shark Hikmat al-ishrāq in philosophy, the last having become a standard text of Islamic philosophy in the traditional schools of Persia. His writings were also one of the influential intellectual elements that made possible the Safavid renaissance in philosophy and the sciences in Persia, and his name continued to be respected and his works studied in the Ottoman and the Mogul empires.


1. One of the few treatises of Quṭb al-Dīn analyzed thoroughly in a European language, is E. Wiedemann, “Ueber eine Schrift ueber die Bewegung des Rollens und die Beziehung zwischen dem Geraden und dem Gekruemmten von Quṭb al Din Mahmud b. Mas’ud al Schirazl,” in Sitzungsherichte der Physikalisch-medizinischen Sozietdt in Erlangen. 58–59 (1926–1927), 219–224.

2. Article on Kutb al-Dīn al-Shlrāzī, in Encyclopaedia of Islam, 1st ed., II, 1167.

3. E. S. Kennedy, “Late Medieval Planetary Theory,” in Isis, 57 , pt. 3 (1966). 367, 373.

4.Ibid., 373–374.


I. Original Works. Quṭb al-Din’s published works are Durrat al-tāj, pt. I, 5 vols., S. M. Mishkāt, ed. (Teheran,1938–1941); pt. II, 5 vols. S. H. Tabasí, ed. (Teheran, 1938–1944); and Sharh Hikmat at-ishrāq (Teheran, 1897).

II. Secondary Literature. See E. S. Kennedy, “Late Medieval Planetary Theory,” in Isis., 57 , no. 3 (1966), 365–378; M. Krause, “Stambuler Handschriften islamischer Mathematiker,” in Quellen und Studien zurGeschichte der Mathematik, Astronomie und Physik, Abt. B, Studien, 3 (1936), 437–532; M. Minovi, “Mullā Qulb Shlrāzī,” in Yād-nāma-ye irānī-ye Minorsky (Teheran, 1969), 165–205; M. T. Mír, Pizishkdn-i nāmī-ye pars (Shiraz, 1969), 110–117; S. H. Nasr, Science and Civili zation in Islam (Cambridge, Mass., 1968), 56 and passim;G. Sarton, An Introduction to the History of Science, II (Baltimore, 1941), 1017–1020; A. Sayili, The Observatory in Islam (Ankara, 1960), passim; H. Suter, “Die Mathe matiker und Astronomen der Araber,” in Abhandlungenzur Geschichte der mathematischcn Wissenschaften (1900), 158; Qadrí Ḥāfiz Ṭuqān, Turāth al-arab al’s al-ilmi fil’ riyāḍiyyāt wa’l-falak (Cairo, 1963), 425–427; and E. Wiedemann, “Zu den optischen Kenntnissen von Qulb alDin al Schíraz,” in Archie für die Geschichte der Naturwissenschaften und der Technik, 3 (1912), 187–193; “Ueber dei Gestalt, Lage und Bewegung der Erde sowie philosophisch-astronomische Betrachtungen von Quṭb alDin ai Schirāzī,” ibid., 395–422; and “Ueber eine Schriftueber die Bewegung des Rollens und die Beziehung zwischen dem Geraden und den Gekruemmten, von Qulb al Din Mahmud b. Mas’ud al Schirāzī,” in Sitzungsberichte der Physikalisch-medizinischen Sozietät in Erlaigen, 58–59 (1926–1927), 219–224.

Seyyed Hossein Nasr

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Quṭb Al-D." Complete Dictionary of Scientific Biography. . 17 Oct. 2018 <>.

"Quṭb Al-D." Complete Dictionary of Scientific Biography. . (October 17, 2018).

"Quṭb Al-D." Complete Dictionary of Scientific Biography. . Retrieved October 17, 2018 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.