Size has been one of the most interesting aspects of dinosaur science to the general public. This article lists the largest and smallest dinosaurs from various groups, sorted in order of weight and length.
Scale diagram comparing a human and the largest known dinosaurs of five major clades
This list excludes unpublished size estimates (such as those for Bruhathkayosaurus, possibly the largest dinosaur of all). In some cases, dinosaurs are known that will be included on this list if/when they are officially described. In addition, weight estimates for dinosaurs are much more variable than length estimates, because estimating length for extinct animals is much more easily done from a skeleton than estimating weight.
Sizes are given with a range, where possible, of estimates that have not been contradicted by more recent studies. In cases where a range of currently accepted estimates exist, sources are given for the sources with the lowest and highest estimates, respectively, and only the highest values are given if these individual sources give a range of estimates.
Size comparison of selected giant theropod dinosaurs
Size by overall length, including tail, of all theropods over 12 meters.
Sauropod size is difficult to estimate given their usually fragmentary state of preservation. Sauropods are often preserved without their tails, so the margin of error in overall length estimates is high. Mass is calculated using the cube of the length, so for species in which the length is particularly uncertain, the weight is even more so. Estimates that are particularly uncertain (due to very fragmentary or lost material) are preceded by a question mark. Each number represents the highest estimate of a given research paper.
Note that, generally, the giant sauropods can be divided into two categories: the shorter but stockier and more massive forms (mainly titanosaurs and some brachiosaurids), and the longer but slenderer and more light-weight forms (mainly diplodocids).
Size comparison of selected giant sauropod dinosaurs
A list of sauropods that reached 30 meters or more in length, including neck and tail.
^ abcdefghijCarpenter, Kenneth (2006). "Biggest of the big: a critical re-evaluation of the mega-sauropod Amphicoelias fragillimus". In Foster, John R.; and Lucas, Spencer G. (eds.). Paleontology and Geology of the Upper Jurassic Morrison Formation. New Mexico Museum of Natural History and Science Bulletin 36. Albuquerque: New Mexico Museum of Natural History and Science. pp. 131–138.
^ abcCalvo, J.O., Porfiri, J.D., González-Riga, B.J., and Kellner, A.W. (2007) "A new Cretaceous terrestrial ecosystem from Gondwana with the description of a new sauropod dinosaur". Anais Academia Brasileira Ciencia, 79(3): 529-41.
^ abLacovara, K; Harris J., Lammana M., Novas F., Martinez R., and Amrosio, A. 2004. An enormous sauropod from the Maastrichtian Pari Aike Formation of southernmost Patagonia. Journal of Vertebrate Paleontology, 24(3) Supplement, 81A
^ abcdeLovelace, David M.; Hartman, Scott A.; and Wahl, William R. (2007). "Morphology of a specimen of Supersaurus (Dinosauria, Sauropoda) from the Morrison Formation of Wyoming, and a re-evaluation of diplodocid phylogeny". Arquivos do Museu Nacional65 (4): 527–544.Cite uses deprecated parameters (help)
^ abHerne, Matthew C.; Lucas, Spencer G. (2006). "Seismosaurus hallorum: Osteological reconstruction from the holotype". New Mexico Museum of Natural History and Science Bulletin36.Cite uses deprecated parameters (help)
^Butler, R.J., P.M. Galton, L.B. Porro, L.M. Chiappe, D.M. Henderson, and G.M. Erickson. (2009). "Lower limits of ornithischian dinosaur body size inferred from a new Upper Jurassic heterodontosaurid from North America." Proceedings of the Royal Society B, 10.1098/rspb.2009.1494
^ abChatterjee, S., and Templin, R.J. (2007). "Biplane wing planform and flight performance of the feathered dinosaur Microraptor gui." Proceedings of the National Academy of Sciences, 104(5): 1576-1580. 
^ abGodefroit, P.; Demuynck, H.; Dyke, G.; Hu, D.; Escuillié, F. O.; Claeys, P. (2013). "Reduced plumage and flight ability of a new Jurassic paravian theropod from China". Nature Communications4: 1394. doi:10.1038/ncomms2389. PMID23340434.edit
^You, H.-L.; Li, D.-Q.; Zhou, L.-Q.; and Ji, Q (2008). "Daxiatitan binglingi: a giant sauropod dinosaur from the Early Cretaceous of China". Gansu Geology17 (4): 1–10.Cite uses deprecated parameters (help)
^Dong, Z. (1997). "A gigantic sauropod (Hudiesaurus sinojapanorum gen. et sp. nov.) from the Turpan Basin, China." Pp. 102-110 in Dong, Z. (ed.), Sino-Japanese Silk Road Dinosaur Expedition. China Ocean Press, Beijing.
^ abTaylor, M.P. (2009). "A Re-evaluation of Brachiosaurus altithorax Riggs 1903 (Dinosauria, Sauropod) and its generic separation from Giraffatitan brancai (Janensh 1914)". Journal of Vertebrate Paleontology29 (3): 787–806. doi:10.1671/039.029.0309.
^Foster, J.R. (2003). Paleoecological analysis of the vertebrate fauna of the Morrison Formation (Upper Jurassic), Rocky Mountain region, U.S.A. New Mexico Museum of Natural History and Science Bulletin, 23. Albuquerque, New Mexico: New Mexico Museum of Natural History and Science.
^Anderson, J. F.; A. Hall-Martin, D. A. Russel. (1985). "Long-bone circumference and weight in mammals, birds, and dinosaurs.". Journal of Zoology (London) (207): 53–61.Cite uses deprecated parameters (help)
^Zhao Xijin, Wang Kebai, & Li Dunjing (2011). "Huaxiaosaurus aigahtens". Geological Bulletin of China30 (11): 1671–1688.
^Lambert, David; and the Diagram Group (1990). The Dinosaur Data Book. New York: Avon Books. p. 60. ISBN0-380-75896-2.Cite uses deprecated parameters (help)
^Naish, Darren; David M. Martill (2001). "Ornithopod dinosaurs". Dinosaurs of the Isle of Wight. London: The Palaeontological Association. pp. 60–132. ISBN0-901702-72-2.Cite uses deprecated parameters (help)
^Kirkland, James I.; Hernández-Rivera, René; Gates, Terry; Paul, Gregory S.; Nesbitt, Sterling; Serrano-Brañas, Claudia Inés; and Garcia-de la Garza, Juan Pablo (2006). "Large hadrosaurine dinosaurs from the latest Campanian of Coahuila, Mexico". In Lucas, S.G.; and Sullivan, Robert M. (eds.). Late Cretaceous Vertebrates from the Western Interior. New Mexico Museum of Natural History and Science Bulletin, 35. Albuquerque, New Mexico: New Mexico Museum of Natural History and Science. pp. 299–315.Cite uses deprecated parameters (help)
^ abcHorner, John R.; Weishampel, David B.; and Forster, Catherine A (2004). "Hadrosauridae". In Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.). The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 438–463. ISBN0-520-24209-2.Cite uses deprecated parameters (help)
^Dodson, Peter (1996). The Horned Dinosaurs: A Natural History. Princeton, New Jersey: Princeton University Press.
^Carpenter, K. (2004). "Redescription of Ankylosaurus magniventris Brown 1908 (Ankylosauridae) from the Upper Cretaceous of the Western Interior of North America". Canadian Journal of Earth Sciences41 (8): 961–986. Bibcode:2004CaJES..41..961C. doi:10.1139/e04-043.
^Galton, Peter M.; Upchurch, Paul, 2004, "Stegosauria" In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd edition, Berkeley: University of California Press. Pp. 344-345
^Carpenter, Kenneth. (1984). "Skeletal reconstruction and life restoration of Sauropelta (Ankylosauria: Nodosauridae) from the Cretaceous of North America". Canadian Journal of Earth Sciences21 (12): 1491–1498. doi:10.1139/e84-154.
Paul, Gregory S. (1997). "Dinosaur models: the good, the bad, and using them to estimate the mass of dinosaurs". Dinofest International1997: 129–154.