SNR Calculator
Signal-to-noise ratio from measured voltages or powers, the linear ratio, ENOB equivalent and a quality verdict.
Bandwidth is half the measurement: noise grows with โBW, so always quote SNR with the bandwidth it was measured in. In a chain, the FIRST stage's noise figure dominates (Friis) โ a quiet preamp at the sensor beats any cleanup later. Averaging N samples buys โN improvement on white noise: 100 averages = +20 dB, free.
SNR Calculator computes signal-to-noise ratio from measured levels, with ENOB equivalent โ free, instant and private in your browser. Audio, sensor and RF people quantifying how clean a chain really is use it to skip the datasheet algebra: type your numbers, read the answer with the substituted formula shown step by step, and share an exact permalink of the calculation.
About SNR Calculator
SNR Calculator computes signal-to-noise ratio from measured levels, with ENOB equivalent using the standard engineering relation: SNR = 20log(Vs/Vn) for voltages, 10log(Ps/Pn) for powers. Worked live: 1 V of signal over 1 mV of noise is 60 dB โ instrument-respectable, ~9.7 effective bits. The result recalculates on every keystroke, the worked-example panel shows your numbers substituted into the formula, and the Copy permalink button encodes the inputs in the URL so a colleague opens exactly your calculation. Everything runs client-side โ nothing you type leaves your device.
How to use SNR Calculator
- 1Enter your values โ the tool starts with realistic defaults for this exact use case, so the worked example is meaningful immediately.
- 2Read the live result and the worked-example panel, which substitutes your numbers into the formula step by step.
- 3Adjust any input to compare scenarios, then use Copy result or Copy permalink to share the calculation.
Why use SNR Calculator?
- โImplements the real formula โ SNR = 20log(Vs/Vn) for voltages, 10log(Ps/Pn) for powers โ with the substitution shown, not a black box
- โBuilt for audio, sensor and RF people quantifying how clean a chain really is
- โCopy result and permalink buttons โ share the exact calculation in a README, forum answer or design review
- โ100% free, no sign-up, runs entirely in your browser (works offline once loaded)
Frequently asked questions
How do you calculate snr?+
Signal-to-noise ratio from measured levels, with ENOB equivalent follows SNR = 20log(Vs/Vn) for voltages, 10log(Ps/Pn) for powers. For example, 1 V of signal over 1 mV of noise is 60 dB โ instrument-respectable, ~9.7 effective bits. The calculator applies the same relation and shows the substituted arithmetic so you can verify every step.
How do I measure the noise level fairly?+
Same bandwidth as the signal measurement, signal source off (not disconnected โ keep the impedance), true-RMS reading. Noise grows with โbandwidth, so an SNR without its bandwidth is meaningless: 60 dB in 20 kHz โ 60 dB in 1 MHz.
Cheapest ways to buy more SNR?+
Average: N readings of white noise gain โN โ 100 averages = +20 dB, free if you have time. Then narrow the bandwidth to just what the signal needs, fix the FIRST stage (Friis: its noise dominates the chain), and only then spend money on exotic parts.
Is the SNR Calculator free and private?+
Yes โ completely free with no sign-up or usage limits, and it runs entirely in your browser: the values you enter are never uploaded or stored on a server.
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