Online dynamics compressor for voice and podcasts
Reduce the gap between the loud and quiet parts of a recording with threshold, ratio, knee, attack and release, or with presets ready for voice.
Drag your audio file here or click to choose it
- .mp3
- .wav
- .flac
- .ogg
- .m4a
- .aac
Use your Google Drive without giving up your privacy
Pick files from your Drive, process them here and save the result to any folder you like. Everything happens in your browser: ShiftAny has no servers of its own.
- Your Google Drive
- Your browserAll processing happens here
- Your Drive or your device
- Your files travel straight between Google and your browser. They never touch a server of ours, because we don’t have any.
- Processing runs on your device, exactly as it does with a file from your computer.
- The app can only access the files you pick and the ones it saves to your Drive. Never the rest.
- Access expires after one hour and is never stored. This browser only remembers your name and email so you can reconnect in one click; you can disconnect at any time.
- Processing
- In your browser
- Upload
- No upload to ShiftAny
- Account
- No sign-up
- Price
- Free
- Input
- MP3, WAV, FLAC, OGG, M4A, AAC
- Output
- MP3, WAV
- Platform
- Web browser
With the quality of SH Core, our own engine: what you hear is exactly what you download.
How to use “Dynamics Compressor”
- Add an audio file to compress (a new one replaces the previous one).
- Choose a preset (voice, instruments, or mix and master) or set the controls.
- Click “Listen live” and fine-tune the Threshold and Makeup while it plays; the “Advanced” view shows how much it compresses at each moment.
- Choose MP3 or WAV, click “Compress dynamics” and download the result.
How to read the advanced view
The large graph shows the last 10 seconds (at ½× speed, the default) from left to right, as in Fruity Limiter. Each column is the true peak of its slice of audio (about 5 ms at 1×, half that on high-density screens), so you see every transient and how the compressor treats it. With “Speed” (¼× to 8×) you choose the scroll speed: faster means fewer seconds on screen and more detail on each hit. Changing it does not erase what has been drawn: it is rescaled to the new window. With “Range” you choose the axis: 32 dB (from +6 to −32 dB, the default) or 24 dB (from +6 to −24 dB), which zooms in further on the peaks.
The signal
- Input peak (purple): the original signalA translucent layer with the input peak. It shows above the green when the compressor pulls a peak down: the more purple, the more compression.
- Output peak (green): what comes outA translucent layer with the output peak, after compression and Makeup. It shows above the purple if the Makeup takes the signal above the original; with Makeup at 0 dB you will never see green on top.
- Blend (grayish green): they matchWhere the two layers overlap their colors blend: that is the part of the signal that passes through unchanged.
The lines
- Gain (makeup − GR)Applied gain: it hangs from the “Makeup” line and drops by as many dB as are being cut at each moment, showing the attack and release.
- MakeupFollows the Makeup dial (output gain). Moving the knobs does not change what has already been drawn: it only affects what plays next.
- ThresholdDrag the line (or use ↑↓ with the graph selected) to move it. With Threshold and Makeup at 0 dB they show as a single white line.
Meters and curve
- INInput peak, from −48 to +6 dBFS, with its peak hold.
- GRGain reduction: it drops from 0 dB as the compressor works.
- OUTOutput peak; it turns red if it goes over 0 dBFS (clipping).
- Transfer curveInput against output: the flatter it gets above the Threshold, the more it compresses. The white dot marks where the signal is.
- When you stop listening, the graph keeps the last thing that played so you can study it.
- Bypass (A/B) compares with the uncompressed signal; the export always uses the settings.
- “Expand” (next to Bypass) takes the graph and all the controls full screen: the graph uses all the free height. Esc goes back.
What a compressor does
When the signal goes over the threshold, the compressor turns it down according to the ratio (at 4:1, every 4 dB over the threshold comes out as 1 dB). The knee softens the way into compression, the attack sets how fast it reacts and the release how fast it lets go. After compressing, the output gain restores the level: it is the only thing that raises it. The compressor is SH Core’s, ShiftAny’s own engine: it sounds the same when you listen and in the file, and at the end of the chain a true-peak limiter guarantees the ceiling (−1 dBTP in MP3, −0.3 dBTP in WAV) without distortion.
Are my files uploaded?
No. ShiftAny Audio processes your audio directly on your device: this tool runs in your browser and never sends your files to any server.
Limits and metadata
ShiftAny sets no duration or size limits: the real ceiling is your device’s memory, because the audio is decompressed to be processed and an hour of stereo takes more than 1 GB. With very long files, we warn you before loading them. The new file contains only the audio: tags (title, artist, cover art) are not copied.
Frequently asked questions
Which preset should I use for a podcast?
“Podcast voice” (threshold −24 dB, 4:1, 5 ms attack, 150 ms release) evens out the voice without it being noticeable; its Auto mode adjusts the threshold and gain to each recording. If it sounds squashed, try “Gentle compression”; for a very steady level, “Radio voice-over”.
How is this different from “Normalize Audio”?
“Normalize Audio” raises or lowers the whole file by the same amount, up to a peak or a loudness. Compressing changes the dynamics: it brings the quiet parts closer to the loud ones. The usual order is to compress and then normalize.
Why does it sound like it is “pumping”?
A very low threshold or a very short release makes the level rise and fall audibly. Raise the threshold, lower the ratio or lengthen the release.