Atomic Radius Calculator
Compare atomic, covalent, and van der Waals radii of elements and calculate bond lengths.
Select Elements
Quick Comparisons:
Estimated Bond Length
268 pm
2.68 Angstrom
1Na Radius
190 pm
2Cl Radius
79 pm
LLarger Element
Na
RSize Ratio
2.41x
Unit Conversions:
Na:
190 pm
1.90 A
0.1900 nm
Cl:
79 pm
0.79 A
0.0790 nm
Types of Atomic Radii
Atomic Radius
Half the distance between nuclei of two identical bonded atoms.
Covalent Radius
Half the distance between nuclei in a covalent single bond.
Van der Waals
Half the minimum distance between non-bonded atoms.
Periodic Trends
Atomic radius decreases across a period (left to right) due to increasing nuclear charge pulling electrons closer. Atomic radius increases down a group due to additional electron shells. These trends help predict chemical behavior and bonding characteristics.