Term: signal-to-noise ratio
https://doi.org/10.1351/goldbook.08282

Definition:
Power of signal divided by power of noise.

Notes:
1) When signal and noise are measured across the same impedance, SNR is often calculated as the root-mean-squared amplitude of the signal divided by the root-mean-squared amplitude of the noise.
2) The value of signal-to-noise ratio may be expressed in decibel (\(\rm{SNR}_{\rm{dB}}\)) as ten times the logarithm to base 10 of signal-to-noise ratio.
3) Initialisms should not be used to denote a quantity in expressions and formulae. \(R_{\rm{S/N}}\) is recommended.

Source: PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 672 (https://doi.org/10.1515/pac-2019-0203)

Citation: 'signal-to-noise ratio' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.08282

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