The reticulated python is the longest snake, but the green anaconda is the heaviest. Ranked by the longest reliably recorded length of any individual, with typical size, weight and conservation status for each.
Pictured: Medusa, a captive reticulated python, from a Guinness World Records video; the species is #1 with a reliably measured wild maximum of 6.95 m (Medusa herself is credited with 7.67 m in captivity).
Rank
Species
Max recorded length (m)
Typical adult length (m)
Max weight (kg)
Region
Venomous
IUCN status
1
Reticulated Python (Malayopython reticulatus)
6.95
1.5–6.5
59
Southeast Asia
No
Least Concern
2
Central African Rock Python (Python sebae)
6.5
3–3.5
91
Sub-Saharan Africa
No
Near Threatened
3
Green Anaconda (Eunectes murinus)
6.32
3–5
97.5
South America
No
Least Concern
4
Southern African Rock Python (Python natalensis)
5.8
2.8–4
65
Southern & East Africa
No
Least Concern
5
Burmese Python (Python bivittatus)
5.79
2.35–5
98
Southeast Asia
No
Vulnerable
6
King Cobra (Ophiophagus hannah)
5.7
3.18–4
12.7
South & Southeast Asia
Yes
Vulnerable
7
Australian Scrub Python (Simalia kinghorni)
5.65
about 3.5
35
Australia
No
Not assessed
8
Cuban Boa (Chilabothrus angulifer)
5.65
up to 4.8
40
Caribbean
No
Least Concern
9
Amethystine Python (Simalia amethistina)
4.72
up to about 4
20
New Guinea & Indonesia
No
Least Concern
10
Indian Python (Python molurus)
4.6
about 3
52
South Asia
No
Near Threatened
11
Yellow Anaconda (Eunectes notaeus)
4.6
3–4
55
South America
No
Least Concern
12
Black Mamba (Dendroaspis polylepis)
4.5
2–3
—
Sub-Saharan Africa
Yes
Least Concern
13
Papuan Python (Apodora papuana)
4.39
3–4
22.5 (avg)
New Guinea
No
Least Concern
14
Boa Constrictor (Boa constrictor)
4.3
0.9–4
27
Americas
No
Least Concern
No matching rows.
Ranking rule: each species is ordered by the longest reliably recorded length of a single individual, as graded in Wikipedia’s “List of largest snakes” and the individual species pages and the papers they cite (Mehrtens, Living Snakes of the World; Barker et al. 2012; Rivas et al. 2024); Guinness World Records and the Reptile Database were used as cross-checks. Lengths are total length including the tail, in metres. Unverified claims are excluded: snakes of 8–10 m, the 9.8 m African rock python, 11.4 m anacondas and the 32 ft reticulated python of 1912 never produced a specimen, and the Oenpelli python (over 4 m, one captive reportedly over 5 m) is left out because its data are too thin. Where a captive record is graded only “somewhat reliable” it is mentioned but does not set the rank (reticulated python Medusa, 7.67 m). The second column is the typical adult range from the same accounts; weights are the heaviest reliably reported animal, so some are captive. Maximum-length claims vary widely between sources, so close rows are near-ties (Southern African rock and Burmese pythons, scrub python and Cuban boa, Indian python and yellow anaconda). The green anaconda is the heaviest snake but only third longest here. Boa constrictor length (4.3 m) is described as “possibly”, not reliable. IUCN categories are those in each Wikipedia infobox and can change at the next Red List review.[1]
The Top 10
#1
Reticulated Python — 6.95 m
The longest snake species, and the only one with a length measured under anaesthesia: a wild female from Balikpapan, Indonesia, was 6.95 m and 59 kg. Guinness World Records credits a captive female, Medusa, with 7.67 m (weight 158.8 kg), the longest snake ever kept in captivity, but Wikipedia’s largest-snakes list grades that figure only “somewhat reliable”, so it does not set the rank. Claims of 8 to 10 m have never been backed by a specimen. A study of more than 1,000 wild Sumatran snakes found a length range of 1.5 to 6.5 m. Least Concern.[2]
#2
Central African Rock Python — 6.5 m
Africa’s largest snake. Wikipedia’s list gives 6.5 m as reliable and 7.5 m as not firmly verified; an alleged 9.8 m animal from Côte d’Ivoire is considered doubtful and is ignored. Adults normally measure 3 to 3.5 m, and only unusually large ones exceed 4.8 m. Weights of 91 kg are reliable, up to 113 kg unverified. Since the species was split from the southern rock python, older records may mix the two. Near Threatened. The video shows a leopard and a rock python.[3]
#3
Green Anaconda — 6.32 m
The heaviest snake in the world rather than the longest. The longest reliably measured specimen listed by Rivas et al. (2024) is 6.32 m; the biggest of 780 animals caught in a seven-year study was 5.21 m and 97.5 kg. Females average about 4.6 m and males about 3 m. Tales of 9 to 11 m anacondas have no skins or bones to back them. Least Concern.[4]
#4
Southern African Rock Python — 5.8 m
Once lumped with the Central African rock python and now a separate species. A length of 5.8 m is rated reliable (6 m not firmly verified), while the longest of 75 females measured in South Africa was 4.34 m and 53.4 kg. Average adults are 2.8 to 4 m, and the heaviest reliable animal weighed 65 kg. Least Concern.[5]
#5
Burmese Python — 5.79 m
A wild python killed in Florida in July 2023 is listed as the longest wild specimen at 5.79 m; a captive female named Baby was corrected to 5.74 m in a 2012 study, which replaced claims of 7 m or more with a measured record. Wild pythons typically reach about 5 m, and the heaviest wild one weighed 98 kg (captive Baby 182.8 kg). Its length is only 1 cm shorter than the Southern African rock python’s, so these are close to a tie. Vulnerable in its native range.[6]
#6
King Cobra — 5.7 m
The longest venomous snake in the world. Wikipedia’s list gives up to 5.7 m for captive animals and 12.7 kg; the species page cites a record of 5.85 m from Mehrtens (1987), which is used here only as a footnote because the more conservative figure is the better documented one. Adults are 3.18 to 4 m. It eats mostly other snakes. Vulnerable.[7]
#7
Australian Scrub Python — 5.65 m
Australia’s longest snake and the Cape York cousin of the amethystine python, which Wikipedia now treats as a separate species. Reports of 7.2 to 8 m are not verified; 5.65 m is rated reliable. Typical adults are about 3.5 m and the largest weights listed reliably are 35 kg. It has not been assessed by the IUCN as its own species. No suitable verified video was found.[8]
#8
Cuban Boa — 5.65 m
The largest snake in Cuba and the West Indies. The biggest individual measured 5.65 m and was estimated at more than 40 kg; lengths above 5 m and weights over 30 kg are described for large animals, and most are shorter, up to 4.8 m. Least Concern. No suitable verified video was found.[9]
#9
Amethystine Python — 4.72 m
The scrub python of New Guinea and Indonesia. Specimens above 5.5 m have been reported but are likely confusion with its Australian relative; 4.72 m is rated reliable and even 4 m animals are considered extremely large. It can reach about 20 kg. Least Concern. No suitable verified video was found.[10]
#10
Indian Python — 4.6 m
Smaller than its close relative the Burmese python. The longest scientifically recorded specimen, from Pakistan, was 4.6 m and 52 kg; 6.4 m and 91 kg are not firmly verified. Most reach about 3 m. Near Threatened.[11]
Wikipedia, “List of largest snakes” and the species accounts for all 14 species, read from raw page text on 2026-10-19 (maximum and typical lengths, weights, IUCN infobox status; reliability grades). Cross-checks: Guinness World Records (longest snake in captivity, Medusa, 7.67 m); Animal Diversity Web, Python sebae. IUCN Red List (iucnredlist.org) categories as quoted in the infoboxes; the Red List site itself was not opened for this post.
Wikipedia, “Reticulated python” (6.95 m and 59 kg under anaesthesia, Sumatra study 1.5–6.5 m); Guinness World Records video, Medusa.
Wikipedia, “Central African rock python” (3–3.53 m, over 6 m reliable); National Geographic video, “Leopards vs. Python Snake”.
Wikipedia, “Green anaconda” (6.32 m, Rivas et al. 2024; 5.21 m and 97.5 kg among 780 animals); BBC Earth, Deadly 60.
Wikipedia, “Southern African rock python” (5.8 m, 65 kg, average 2.8–4 m); Earth Touch video.
Wikipedia, “Burmese python” (5.79 m wild, 98 kg; Barker et al. 2012, 5.74 m); Virginia Zoo video.
Wikipedia, “King cobra” (3.18–4 m; record 5.85 m from Mehrtens 1987; 5.7 m and 12.7 kg in the list); BBC Earth, Deadly 60.
Wikipedia, “Australian scrub python” and “List of largest snakes” (5.65 m reliable, 35 kg).
Wikipedia, “Cuban boa” (5.65 m largest individual, more than 40 kg).
Wikipedia, “Amethystine python” (4.72 m reliable, up to 20 kg).
Wikipedia, “Indian python” (4.6 m and 52 kg from Pakistan); National Geographic India video. Rows 11–14: Wikipedia, “Yellow anaconda” (4.6 m), “Black mamba” (4.3–4.5 m), “Papuan python” (4.39 m) and “Boa constrictor” (up to 4.3 m).
