About

This Audio Reverser performs a complete time-inversion of digital audio signals directly in your browser. Unlike simple playback tricks, this tool physically rewrites the sample order of the audio file, generating a downloadable, high-quality WAV file. This process is often used in Musique Concrète, sound design for horror films, or to reveal hidden "backmasking" messages in music.

The tool decodes compressed formats (like MP3) into raw PCM data, flips the array of amplitude values, and re-encodes it into a lossless container. The transformation is mathematically exact, preserving the spectral characteristics of the original sound while reversing its temporal envelope.

Formulas

Digital audio is stored as a sequence of discrete samples. To reverse audio, we map the input signal x[n] to an output signal y[n] where the time index is inverted relative to the total length N.

y[n] = x[N − 1 − n]

Where:

y[n] = The amplitude at sample n in the reversed file.
N = Total number of samples (Duration × Sample Rate).
n = The current sample index (0 to N−1).

Reference Data

Parameter	Specification
Processing Method	Client-Side PCM Inversion
Input Formats	MP3, WAV, OGG, AAC, FLAC
Output Format	WAV (16-bit PCM, 44.1kHz / 48kHz)
Max Duration	Dependent on RAM (typ. 10-15 mins)
Sample Accuracy	100% Lossless Reversal
Bit Depth	16-bit (Standard CD Quality)
Channels	Mono / Stereo Support

Frequently Asked Questions

The reversing process itself is lossless. However, if you upload a compressed file (like MP3), it is decoded to raw audio and then saved as an uncompressed WAV. You won't lose further quality, but the file size will be larger than the MP3 original.

WAV is a lossless, uncompressed format that is easy to generate in a browser environment. Encoding to MP3 requires heavy, patent-encumbered libraries that can slow down your device. WAV ensures the highest fidelity for your reversed audio.

Yes, but it depends on your device's available RAM. A 5-minute song uses about 50-100MB of memory to process. Extremely long files (audiobooks, podcasts) might crash the browser tab.

No. All processing happens locally in your browser using the Web Audio API. Your files never leave your device.