All things · Atoms & Molecules
Water molecule: how big is it?
Water molecule is about 275 pm. In everyday terms, that is ≈ 2.6 hydrogen atoms.
- Size
- 275 pm
- In metres
- 2.75 × 10⁻¹⁰ m
- Everyday comparison
- ≈ 2.6 hydrogen atoms
- Chapter
- Atoms & Molecules
Did you know?
One oxygen and two hydrogens. A single drop of water holds about 1.7 sextillion of them.
How it compares
- About 2.6× bigger than Hydrogen atom (106 pm).
- Roughly the same size as Gold atom (288 pm).
Other things of a similar size
- Hydrogen atom 106 pm
- Gold atom 288 pm
- Glucose molecule 900 pm
- DNA (width) 2 nm
- Haemoglobin 5.5 nm
- Antibody 12 nm
Sizes are rounded, typical values drawn from standard reference sources, including NIST/CODATA physical constants and NASA's planetary fact sheets. Real objects vary; see About for how sizes are chosen.