Ry to J Converter
Convert Rydbergs to Joules instantly.
Free online converter with accurate results and clear explanations.
Last updated · How we build & check our tools
Frequently Asked Questions
Common questions about the Ry to J Converter
Unit of energy in atomic physics: 1 Ry = 13.6 eV = 2.18 × 10⁻¹⁸ J. Hydrogen ionization energy.
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Sources & References
International System of Units (SI): energy, work and heat
Energy, work and heat is measured in the joule (J); 1 cal = 4.184 J. Conversions between SI and other units use exact, internationally agreed factors maintained by NIST.
International System of Units (SI)
Authoritative definitions for energy, work and heat, from the BIPM SI Brochure (9th edition), the defining reference for the SI.