English: The size and growth of the whale shark, showing changes in body proportions as they grow; represented by various individuals with body measurements reported in the literature. Showing a small 55 centimetres (22 in) newborn pup, three juveniles at 1.48 metres (4.9 ft), 3.60 metres (11.8 ft), and 5.62 metres (18.4 ft), a 9 metres (30 ft) average fully grown adult male, a 12.1 metres (40 ft) adult female, a generic average fully grown 14.5 metres (48 ft) adult female, and an exceptionally large adult female with a precaudal length of 15 metres (49 ft). For more details, see below.

• The smallest individual in the chart is based on measurements of a 'pup' described by Wolfson (1983), reported as 55 cm in length.^[1]

• The 'juvenile' whale sharks are based on measurements for a 1.48 m unsexed individual (Paul, 2012), a 3.60 m female (Somasekharan Nair et al., 1986), and a 5.62 m female (Silas & Rajagopalan, 1963).^[2][3][4]

• Evidence from mainly male whale sharks suggests they are sexually mature at around 8-9 m in length (9 m shown here). Females might sexually mature at a similar size or larger.^[5][6][7] In 2020, it was shown that whale sharks are sexually dimorphic regarding body size, with males reaching smaller sizes than females. Meekan et al. (2020) estimated that males reach an average asymptomatic length of 8-9 m; this is an average, not the maximum possible male size. Meekan et al. (2020) had less data for females, but estimated an average asymptomatic length of ~14.5 m. However, this value lowered to ~12.1 m if data from aquarium whale sharks were included.^[8]

• The large female silhouettes are based primarily on measurements of whale sharks reported by Kaikini et al. (1959), Devadoss et al. (1989), and inspired by images of large females seen around the Galapagos.^[9][10]

• The largest size possible for whale sharks is uncertain. Various reports suggest individuals can reach ~18-20 m, but most lack detailed measurements or documentation. The largest silhouette is scaled to 15 m standard length (precaudal length), based on an individual reported by Borrell et al. (2011). The total length was not documented; the authors estimated it at 18.8 m using an equation.^[11] McClain et al. (2015) considered this whale shark as the largest reliably measured.^[12]

• Human diver scaled to ~180 cm (5 ft 11 in). Silhouette extracted from File:Sperm_whale_size.svg.

Where possible, silhouettes are based on published measurements of individual whale sharks and online photos. Shark total length can be measured in several ways, including along the body’s curves, with the caudal fin fully stretched, with the caudal fin in a naturalistic posture, or calculated from other measurements such as precaudal or fork length using equations. Unfortunately, reports do not always state which method was used.

Because these methods can produce different results, silhouettes drawn from available measurements may not match the reported total length on the metre grid. For example, Kaikini et al. (1959) reported a whale shark at 12.1 m total length, with a 9.84 m precaudal length and a 2.31 m upper caudal fin. Reaching 12.1 m requires an unusually shallow tail angle, suggesting the original total length was measured with the tail stretched or along the body’s curves.