Which animal has the longest gestation period on this chart?

Of the species listed here the horse is longest at about 340 days, ahead of the cow at 283 days. Across all mammals the African elephant is longest at roughly 645 days.

Which animal has the shortest gestation period?

The rabbit, at about 31 days. Cats and dogs follow at roughly 64 and 63 days, which is why whelping and kindling preparation has to start within weeks of mating.

Why do the figures differ from other gestation charts?

Different sources use different breeds, herd data and starting points. Some count from mating, others from ovulation or embryo transfer, which shifts the average by several days.

What does the range column mean?

It is the window in which a healthy birth normally happens for that species, not a margin of error. Plan for the earliest date rather than the average.

Can I print this gestation chart?

Yes. Use the print button above the table and the page prints the heading, the full table and the site address only, with navigation, filters and ads removed.

Animal Gestation Chart

Average gestation length for every species on the site, with the normal range, the equivalent in months and typical litter size. Sort any column or filter by category.

Search species

Gestation length by species, sortable and filterable
		Range	Months	Litter size
Virginia opossum	13	12–14	0.4 months	8-9 joeys	Wild animals
Hamster gestation calculator	16	15–18	0.5 months	6-8 pups	Rodents and small pets
Mouse gestation calculator	20	19–21	0.7 months	5-8 pups	Rodents and small pets
Rat gestation calculator	22	21–23	0.7 months	6-12 pups	Rodents and small pets
Gerbil gestation calculator	25	24–26	0.8 months	4-8 pups	Rodents and small pets
Rabbit gestation calculator	31	28–33	1.0 months	4-12 kits	Pets
Red kangaroo	33	30–36	1.1 months	1 joey	Wild animals
Ferret gestation calculator	42	38–44	1.4 months	6-8 kits	Rodents and small pets
Grey squirrel	44	40–45	1.4 months	2-4 kits	Wild animals
Red fox	52	49–55	1.7 months	4-6 kits	Wild animals
Dog gestation calculator	63	58–68	2.1 months	1-12 puppies	Pets
Cat gestation calculator	64	61–67	2.1 months	3-5 kittens	Pets
Guinea pig gestation calculator	68	59–72	2.2 months	2-4 pups	Rodents and small pets
Tiger gestation calculator	105	93–112	3.4 months	2-4 cubs	Wild animals
Lion gestation calculator	110	105–115	3.6 months	2-4 cubs	Wild animals
Chinchilla gestation calculator	111	105–118	3.6 months	1-3 kits	Rodents and small pets
Pig gestation calculator	114	112–116	3.7 months	8-12 piglets	Livestock
Sheep gestation calculator	147	144–152	4.8 months	1-2 lambs	Livestock
Goat gestation calculator	150	145–155	4.9 months	1-3 kids	Livestock
White-tailed deer	200	187–222	6.6 months	1-2 fawns	Wild animals
Grizzly bear	235	180–250	7.7 months	1-3 cubs	Wild animals
Chimpanzee	237	230–240	7.8 months	1 infant	Wild animals
Hippopotamus	240	225–250	7.9 months	1 calf	Wild animals
Gorilla	257	250–270	8.4 months	1 infant	Wild animals
Human	280	259–294	9.2 months	1 baby	Wild animals
Cow gestation calculator	283	279–292	9.3 months	1 calf	Livestock
Water buffalo gestation calculator	310	300–320	10.2 months	1 calf	Livestock
Horse gestation calculator	340	320–370	11.2 months	1 foal	Livestock
Blue whale	340	330–360	11.2 months	1 calf	Wild animals
Alpaca gestation calculator	345	335–355	11.3 months	1 cria	Livestock
Llama gestation calculator	350	330–365	11.5 months	1 cria	Livestock
Donkey gestation calculator	365	340–390	12.0 months	1 foal	Livestock
Dolphin	365	340–380	12.0 months	1 calf	Wild animals
Zebra	375	360–390	12.3 months	1 foal	Wild animals
Manatee	380	365–400	12.5 months	1 calf	Wild animals
Camel gestation calculator	395	390–410	13.0 months	1 calf	Livestock
Giraffe gestation calculator	430	400–460	14.1 months	1 calf	Wild animals
Walrus	460	450–480	15.1 months	1 calf	Wild animals
White rhinoceros	490	480–500	16.1 months	1 calf	Wild animals
Sperm whale	530	480–590	17.4 months	1 calf	Wild animals
Asian elephant gestation calculator	617	600–640	20.3 months	1 calf	Wild animals
African elephant gestation calculator	645	640–660	21.2 months	1 calf	Wild animals

https://animalgestationcalculator.com

How to read this chart

The average days column is the figure the calculators use, and it is the midpoint of normal births rather than a deadline. The range column shows the window in which healthy young usually arrive, so plan for the earliest date in that window. Months are an approximation at 30.44 days per month and are there for quick conversation, not for scheduling. Litter size explains part of the range: species carrying several young tend to give birth slightly earlier than the average suggests, while a single large offspring often runs a few days late.

Longest and shortest gestation periods

The longest gestation on this chart belongs to the african elephant gestation period at 645 days, and the shortest to the virginia opossum gestation period at 13 days. Long gestations produce young that stand and follow the mother within hours, which is essential for grazing animals in the open. Short gestations produce blind, helpless young that finish developing in a nest, so the mother invests in nursing rather than in pregnancy.

Gestation chart questions

Every figure is an average from published breed data. Individual animals vary; results are for planning and are not veterinary advice.