---
title: "Does platinum float in water? No"
description: "Platinum sinks — its density is 21,450 kg/m³ against water's 1,000. Why density and not weight decides it."
url: https://atoneplace.net/does-it-float/platinum/
site: "At One Place"
---

# Does platinum float?

**Does platinum float?: No**

21,450 kg/m³ against water's 1,000

Platinum sinks. At 21,450 kg/m³ it is 21.45 times denser than water.

## Why

Floating is decided by density alone — mass divided by volume — compared against the fluid. Weight has nothing to do with it directly: a 200-tonne ship floats and a 2-gram pebble sinks, because the ship encloses enough air to bring its average density below that of water. That is also the only reason a steel hull works.

## The numbers

- **Density:** 21,450 kg/m³
- **Relative to fresh water:** 21.450×
- **Floats in fresh water:** No
- **Floats in seawater:** No

## Compared with other materials

| Material | Density | Floats |
| --- | --- | --- |
| mercury | 13,534 kg/m³ | No |
| tungsten carbide | 14,900 kg/m³ | No |
| tungsten | 19,250 kg/m³ | No |
| gold | 19,300 kg/m³ | No |
| platinum ← | 21,450 kg/m³ | No |

## Common questions

### Does platinum float in water?

No — at 21,450 kg/m³ it is denser than water's 1,000.

### Does weight decide whether something floats?

No, density does. A 200-tonne ship floats and a small pebble sinks, because the ship encloses enough air to bring its average density below water.

## Related pages

- [Platinum properties](https://atoneplace.net/material/platinum/)
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## Sources

- Wikidata — Wikimedia Foundation (https://www.wikidata.org/) [CC0 1.0]