How big is Lion?
Lion: 2.1 m (6.89 ft). Measured as head-and-body length — an adult male (1.7–2.5 m).
Source: Wikipedia — Lion
Where it sits
Among the 23 animals on this page lion ranks 17th from the top by size. The largest in the group is blue whale at 29.9 m, which is 14.2× the size of lion, while the smallest, honey bee, is 13 mm.
Stand an adult of 1.7 m beside it and the ratio is 1.24×: you would need 1 people stacked head to foot to match its size.
In everyday distances
It fits inside a football pitch 50 times over — a pitch is about 105 m and lion is only 2.1 m.
Walking at an easy 1.4 m/s you cover 2.1 m in 1.5 seconds. A jet at 900 km/h covers it in 8 milliseconds.
Next to its neighbours in size
The nearest thing larger than it in this collection is polar bear at 2.5 m (8.2 ft), 1.19× the size. Note the two figures are not the same measurement: for lion it is head-and-body length, for polar bear it is body length.
The nearest thing smaller is human adult at 1.7 m (5.58 ft), so lion is 1.24× as big as it. They sit in the same group.
Against fixed yardsticks
Against three fixed yardsticks — Eiffel Tower (330 m) is 157× the size of lion; blue whale (29.9 m) is 14.2× the size of lion; Earth (12,742 km) is 6,067,619× the size of lion.
How this figure was taken
Animal sizes vary from one individual to the next, so each figure says which individual or average it describes. Heights are taken at the shoulder or standing; lengths run nose to tail tip unless stated.
How the sizes are taken. Each figure says what it measures — height, length, diameter or elevation — and for which individual or convention. Everything is drawn standing upright on one baseline so a single scale holds, including things that are long rather than tall. Values come from the linked Wikipedia article for each item.
Read the rest — common questions
How big is the lion?
2.1 m (6.89 ft), measured as head-and-body length: an adult male (1.7–2.5 m).
Where does the lion rank among animals?
Number 17 of 23 on this site, from blue whale at 29.9 m down to honey bee at 13 mm.
What is the next size up?
Polar bear, at 2.5 m, is 1.19× the size.
What is the next size down?
Human adult, at 1.7 m, is 1.24× smaller.
How reliable is the figure?
It is taken from the cited Wikipedia article and states its basis (an adult male (1.7–2.5 m)). Values are rounded, and where individuals differ the figure is a representative one, so expect small differences from other sources.