Sampling Alias Frequency Calculator
Fold a single real sinusoidal input into the first Nyquist interval at an entered sample rate.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Remove complete sample-rate multiples and reflect frequencies above Nyquist into the nonnegative real-signal baseband.
r=input mod sample rate; alias=min(r,sample rate−r)
Worked example
A 70 kHz real sinusoid sampled at 48 kHz appears at 22 kHz. A 48 kHz sinusoid samples to a DC-valued sequence depending on phase.
Assumptions and input details
Ideal instantaneous uniform sampling of one sine, with no anti-alias filtering. Frequency folding does not preserve an arbitrary phase or complex-signal orientation; near-exact multiples depend on floating-point precision.
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
SI prefixes are explicit: for example, milli means one thousandth, micro one millionth and kilo one thousand. Changing a unit changes the interpretation of the entered number.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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