---
title: "Black mamba vs king cobra — size, weight and speed compared"
description: "King cobra is 3.8× black mamba on weight. Compared on 3 measured properties, with the full range and a source for each."
url: https://atoneplace.net/vs/black-mamba-vs-king-cobra/
site: "At One Place"
---

# Black mamba vs King cobra

**Black mamba vs king cobra: King cobra is larger on weight**

King cobra is 3.8× black mamba on weight.

A black mamba and a king cobra can be compared on 3 measures. The figures below are typical adult or full-size values, with the larger of the two in bold.

## Side by side

*Larger value in bold. Ranges reflect genuine variation, not uncertainty.*

|  | Black mamba | King cobra |
| --- | --- | --- |
| Weight | 1–3.1 kg | 4–12.7 kg |
| Length | 2–4.3 m | 3–5.85 m |
| Typical lifespan | 10–20 yr | 17–22 yr |

## What the numbers say

- King cobra is 3.8× black mamba on weight.
- King cobra is somewhat greater than black mamba on length — about 1.5×.
- King cobra is 1.8× black mamba on typical lifespan.

*Weight compared.*

- King cobra: 4–12.7 kg
- Black mamba: 1–3.1 kg

## Black mamba

The fastest snake and Africa's longest venomous one; it is named for the black inside of its mouth, not its colour.

## King cobra

The longest venomous snake, delivering enough neurotoxin in one bite to kill an elephant.

> This is a comparison of published measurements, nothing more. It describes how two things differ on measures that have been recorded; it does not predict how they would fare against each other in any situation.

## Common questions

### Which is bigger, black mamba or king cobra?

King cobra is 3.8× black mamba on weight. Both figures are typical values; the full range for each is in the table above.

### How do black mambas and king cobras compare on length?

Black mamba: 2–4.3 m. King cobra: 3–5.85 m. King cobra is somewhat greater than black mamba on length — about 1.5×.

### How do black mambas and king cobras compare on typical lifespan?

Black mamba: 10–20 yr. King cobra: 17–22 yr. King cobra is 1.8× black mamba on typical lifespan.

## Related pages

- [Domestic cat vs king cobra](https://atoneplace.net/vs/domestic-cat-vs-king-cobra/)
- [Black mamba vs peregrine falcon](https://atoneplace.net/vs/black-mamba-vs-peregrine-falcon/)
- [Black mamba vs mallard](https://atoneplace.net/vs/black-mamba-vs-mallard/)
- [Black mamba vs platypus](https://atoneplace.net/vs/black-mamba-vs-platypus/)

## Sources

- Wikidata — Wikimedia Foundation (https://www.wikidata.org/) [CC0 1.0]
- Smithsonian National Museum of Natural History — Smithsonian Institution (https://naturalhistory.si.edu/)