Precise ramping
Uses the Web Audio API's sample-accurate linear and exponential ramp scheduling.
Frequency Sweep Generator
Play a tone that sweeps from a start frequency to an end frequency over a chosen duration, linear or logarithmic, with a live marker showing where you are.
20 Hz
20 Hz20,000 Hz
Live frequency marker
Watch a marker move across the audible scale in sync with the sweeping tone.
Private by design
Everything runs locally in your browser. Nothing is recorded, uploaded, or saved.
How to use the frequency sweep generator
This free online sweep generator glides an oscillator from a start frequency to an end frequency over a duration you choose, using the Web Audio API's built-in ramp scheduling for a smooth, accurate sweep.
- Set start & end frequencyEnter the frequency in Hz where the sweep should begin and finish.
- Choose duration & typePick how many seconds the sweep should take, and linear or logarithmic pacing.
- Play and watchPress play to hear the sweep while the marker and readout track the current frequency.
Linear vs. logarithmic sweeps
Both sweep types move an OscillatorNode's frequency parameter from a start value to an end value over time, but they follow different curves.
Linear sweep
Frequency changes by a constant number of Hz per second, using linearRampToValueAtTime. Because pitch perception is logarithmic, a linear sweep sounds like it spends more time in the higher octaves.
Logarithmic sweep
Frequency changes by a constant number of octaves per second, using exponentialRampToValueAtTime. This matches how we perceive pitch, so the sweep sounds evenly paced from low to high.
The moving marker
While the tone plays, a marker moves across a scale from 20Hz to 20,000Hz using a logarithmic position, matching the current frequency calculated from elapsed time and sweep type.
Common use cases
Sweeps like this are used to audition speaker frequency response, hunt for rattles and resonances, test subwoofer extension, and for acoustic room measurements.
Frequency sweep FAQ
Quick answers about sweep types, scheduling, and speaker safety.
What is a frequency sweep used for?
Frequency sweeps are used to test speaker frequency response, find resonances and rattles, check subwoofer range, and for room acoustic testing.
What's the difference between linear and logarithmic sweeps?
A linear sweep changes frequency at a constant rate in Hz per second, so it spends more perceived time in the high end. A logarithmic sweep changes at a constant rate in octaves per second, which sounds more evenly paced across the audible range.
How is the sweep generated?
It uses the Web Audio API's OscillatorNode with linearRampToValueAtTime for linear sweeps and exponentialRampToValueAtTime for logarithmic sweeps, scheduled precisely against the audio clock.
Can I sweep from a high frequency down to a low one?
Yes. Set the start frequency higher than the end frequency and the sweep will descend instead of ascend.
Is this safe for my speakers?
Very low or very high frequencies at high volume can stress small speakers. Start at a moderate volume and lower it further for sweeps that include sub-bass or very high frequencies.