English: The size and growth of the whale shark (Rhincodon typus), represented by various individuals reported in the literature. A small 55 centimetres (22 in) pup, a 5.62 metres (18.4 ft) juvenile, a generic 9 metres (30 ft) young adult, a large 12.1 metres (40 ft) adult, and an exceptionally large adult with a precaudal length of 15 metres (49 ft).

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

• The 'juvenile' individual is based on measurements in Silas & Rajagopalan (1963), reported as 5.62 m.^[2]

• Evidence from mainly male whale sharks suggests that they are sexually mature at around 8-9 m in length (9 m shown here). Females might mature at a similar size or larger.^[3][4][5] 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 length of 8-9 m; this is an average, not the maximum possible male size. There was less data for females, but Meekan et al. (2020) estimated an average of ~14.5 m. However, this value lowered to ~12.1 m if aquarium whale sharks were included.^[6]

• The 'large adult' silhouette is based primarily on measurements of a whale shark reported by Kaikini et al. (1959) and inspired by images of large females seen around the Galapagos.^[7]

• The largest size possible for whale sharks is uncertain. Reports suggest individuals around ~18-20 m, but many of these reports 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 the total length at 18.8 m using an equation.^[8] McClain et al. (2015) considered this whale shark as the largest reliably measured.^[9]

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

Where possible, the silhouettes are scaled to published measurements of various individuals reported in scientific literature and influenced by whale shark images found online.

Measuring a sharks total length is challenging and there are several ways it can be done. Unfortunately, each version of total length produces somewhat different results and shark reports do not always state which version was used.

• Measure the whole shark by running a tape along the body's curves.

• Measure by stretching the caudal fin to the maximum possible (sometimes referred to as stretched total length).

• Some reports calculate the total length by adding the length of the caudal fin to the precaudal length, or my using equations to estimate total length from smaller body measurements, like precaudal and fork lengths. These equations do not always state which version of total length is being estimated.

• Try and pose the shark's tail fin in a natural position and measure in a straight line. However, for large sharks, this method is difficult to achieve.^[10]

The first three methods artificially increase the shark's total length compared to how the shark measures in a straight line with the caudal fin in a natural posture. The natural posture of the caudal fin is difficult to be confident about.

The silhouettes that are based on specific individuals are drawn using the measurements available and not simply scaled to the reported total length. Therefore, the total length of the silhouette might not align with the corresponding total length on the meter grid.

For example, the whale shark reported by Kaikini et al. (1959) was reported at 12.1 m in total length, the precaudal length was reported at 9.84 m, and the upper caudal fin was 2.31 m. Reaching the reported total length of 12.1 m would require the upper caudal fin to be illustrated at a very shallow angle. This might imply the shark's total length was measured with the caudal fin stretched-out or over the body's curves.