Does density decide floating or sinking?

People keep mentioning density when talking about floating. Is it really the most important factor?

Yes, density is crucial. It’s the ratio of mass to volume, and it decides if an object displaces enough water to float.

Adrian said:
Yes, density is crucial. It’s the ratio of mass to volume, and it decides if an object displaces enough water to float.

Exactly. If an object is less dense than water, it’ll always float, regardless of its weight.

This is why icebergs float—they’re less dense than seawater, even though they’re massive.