Free · Physics models
Signal-to-Noise Ratios and Decibel Forms
Convert simple positive ratios, power or voltage decibel ratios, and a mean-to-deviation statistic.
- Formula & worked example
- Private in your browser
- No signup
Calculator inputs
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How to use this calculator
- Enter the known values in the units shown. Results update as you type.
- Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
- Use the worked example to check the method. Reset restores the starting fields.
Private by default
Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.
Formula and method
pSNR = 10.000. This worked example uses the displayed units and declared assumptions.
SNR = sig / noi; bSNR = signal - noise ; pSNR = if_else(SNRtype < 1, 0, 10 * log10(pSignal/pNoise)); vSNR = if_else(SNRtype < 1, 0, 20 * log10(vSignal/vNoise)); mSNR = signal_mean / sDeviation ; mSNR2 = signal_mean^2 / sDeviation^2
Worked example
Enter these known values and leave the other values blank.
- Type of SNR
- 1
- Signal
- 10 W
- Noise
- 1 W
- Signal-to-noise ratio
- 10 dB(s)
Assumptions and limitations
- Power ratios use 10 log10 and voltage ratios use 20 log10 only for equal impedances. Subtract dB quantities only when they share a reference. Mean/deviation is a statistical ratio whose square is another convention; it is not automatically an electrical power SNR.
- Clear an unknown to solve a supported inverse; keep known values fixed with locks. Singular or underdetermined inverses may remain incomplete.
Common questions
What assumptions apply?
Power ratios use 10 log10 and voltage ratios use 20 log10 only for equal impedances. Subtract dB quantities only when they share a reference. Mean/deviation is a statistical ratio whose square is another convention; it is not automatically an electrical power SNR.
Which unknowns can I solve?
Editable controls preserve the supported captured inverse branches. Clear the desired unknown and provide enough independent known quantities; singular or underdetermined inverses may remain incomplete.
References
Power ratios use 10 log10 and voltage ratios use 20 log10 only for equal impedances. Subtract dB quantities only when they share a reference. Mean/deviation is a statistical ratio whose square is another convention; it is not automatically an electrical power SNR. Clear an unknown to solve a supported inverse; keep known values fixed with locks. Singular or underdetermined inverses may remain incomplete.