Create smooth fade-in and fade-out transitions with multiple curve types: linear, exponential, logarithmic, S-curve, and ease-in-out. Adjustable duration and visual envelope preview.
Apply fade-in and fade-out effects to your audio files. Set the duration for each fade, choose a curve shape, linear, exponential, or logarithmic, and preview the result. Fades smooth out abrupt starts and endings, making clips sound polished and professional.
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Generate beautiful waveform visualizations from audio files. Choose from bars, mirror, line, or circular styles. Customize colors and export as PNG.
Trim, cut, and slice audio files with interactive waveform visualization. Drag handles to select portions, use keyboard shortcuts, zoom and pan, preview selection before export. Supports MP3, WAV, OGG, AAC.
Convert audio files between WAV, MP3, OGG, AAC, M4A, FLAC formats online. Adjust bitrate and quality settings. Free browser-based conversion with no file uploads to servers.
A song clip for a video starts and ends abruptly and needs smooth fades.
Input
clip.mp3 · fade-in 1.5 s · fade-out 3 s · exponential
Output
Gentle ramp up and a natural-sounding tail
An exponential curve matches how we perceive loudness, so fades sound smooth rather than the unnatural rush a linear ramp gives. Clean fades remove the jarring edits that cheapen a video.
Apply fade-in and fade-out effects to your audio files. Set the duration for each fade, choose a curve shape, linear, exponential, or logarithmic, and preview the result. Fades smooth out abrupt starts and endings, making clips sound polished and professional.
Fade out one track and fade in the next for seamless playlist listening.
Gently bring background music in and out under a speaker without jarring cuts.
Audio Fade In/Out applies volume envelopes to the start and end of a clip. You choose a Fade Type (Fade In Only, Fade Out Only, or Both), set independent durations for each with a slider that runs from 0.1s in 0.1-second steps, and pick a curve for each fade from four options: Linear (constant rate), Exponential (x-squared ramp, fast start / slow finish, the recommended default), Logarithmic (slow start / fast finish, computed as 1-(1-x)^2), and S-Curve (a smoothstep x^2*(3-2x) eased at both ends). The slider's upper bound is capped at min(duration/2, 30s), and when you load a file any preset fade longer than half the clip is automatically reduced, so a fade-in and fade-out can never overlap in the middle of a short clip. On load the file is decoded with the Web Audio API's decodeAudioData (with an iOS-Safari AudioContext.resume() fallback), which also drives a live canvas that plots the exact fade envelope as a 0-100% volume curve with shaded blue fade-in and pink fade-out regions.
There is an important behavioral distinction worth knowing before you rely on a specific curve. The on-screen canvas preview renders all four curve shapes faithfully using the formulas above, but the in-browser audio preview is simpler: its GainNode automation only distinguishes exponential (an exponentialRampToValueAtTime) from everything else (a linearRampToValueAtTime), so selecting Logarithmic or S-Curve sounds the same as Linear when you hit Preview. The preview itself is fully scrubbable, it resumes from the playback position you seek to and recomputes the gain ramp from that point, so you can audition just the tail of a long fade without playing the whole track.
The downloaded file is produced by ffmpeg.wasm, not the Web Audio graph: fadeAudio runs FFmpeg's afade filter as `afade=t=in:st=0:d=<fadeIn>,afade=t=out:st=<duration-fadeOut>:d=<fadeOut>`. Be aware that the curve selection is not forwarded to this export step, so the rendered output always uses FFmpeg afade's default (triangular/linear) shape regardless of whether you picked Exponential, Logarithmic, or S-Curve, the curve picker currently affects the visualization and the live preview rather than the exported audio. Export is offered in MP3, WAV, or OGG (with a real-time FFmpeg progress percentage), and the result is named faded_<originalname>.<format>. Everything runs locally in the browser; no audio is uploaded to a server.
Exponential fades sound most natural to human ears because our perception of loudness is logarithmic. Linear fades are simpler and work fine for short durations.
Yes. Set either the fade-in or fade-out duration to zero to skip that fade.
Audio is decoded and processed locally with the Web Audio API. Your files are never uploaded to a server.