Free Analyzer

Hi-Res Audio Fraud Detector

Is your "192 kHz hi-res" file actually an upsampled 44.1 kHz recording? Drop any file to get a real frequency spectrum via FFT. A genuine hi-res master has continuous energy above 22 kHz; a fake cuts off sharply at the original master's Nyquist limit with nothing above the brick wall.

My analyses

Every checked file lands here automatically. Stays on this device only.

Verdict
Awaiting file Drop an audio file below to check it.
Highest real content - Where the spectrum drops below the noise floor.
File format - Sample rate x channels x duration.

All analysis is local. Files never leave your device.

How to read the spectrum

What to look for

A genuine hi-res recording (96 kHz or 192 kHz) shows continuous energy extending above 22 kHz, though the level drops with frequency due to natural program-content rolloff. The key is no abrupt brick-wall cutoff below 22 kHz.

A fraudulently upsampled file shows a sharp, near-vertical dropoff at 20-22 kHz, the fingerprint of the original 44.1 / 48 kHz recording's anti-aliasing filter. Especially common with "hi-res" releases on some stores.

What it cannot prove

Even if a file has genuine hi-res content above 22 kHz, that doesn't automatically mean it sounds better than a well-mastered 16/44.1 file. The source master quality matters more than the format.

This tool analyses format authenticity only. A 96 kHz file genuinely recorded and mastered at 96 kHz is authentic. One mastered at 44.1 and exported at 96 kHz is a storage waste.

Audio formats and what their spectrograms should look like

Sample rate is the upper bound; Nyquist (rate ÷ 2) is the highest frequency a format can encode. Genuine 192 kHz files have energy above 22 kHz; fakes cut off sharply at the original master's Nyquist limit.

FormatSample rateNyquistSpectrogram tells
MP3 320 kbps44.1 kHz22.05 kHzHard cutoff around 16-19 kHz from the codec lowpass.
AAC 256 kbps44.1 kHz22.05 kHzCutoff near 19-20 kHz; cleaner than MP3.
CD (Red Book)44.1 kHz22.05 kHzBrick wall at 22 kHz. Nothing above.
DVD-Audio / pro standard48 kHz24 kHzBrick wall just below 24 kHz.
"Hi-Res" 24/88.288.2 kHz44.1 kHzGenuine: tapered roll-off into 30+ kHz.
"Hi-Res" 24/9696 kHz48 kHzGenuine: continuous energy past 22 kHz.
"Hi-Res" 24/192192 kHz96 kHzGenuine: reaches 40 kHz+. Fakes show the 22 kHz wall.
DSD64 (SACD)2.8 MHz (1-bit)~28 kHz audioRising noise floor above 25 kHz - DSD signature.
DSD128 / 2565.6 / 11.3 MHz~50 / ~100 kHzCleaner band. Same rising noise above the audible limit.

FAQ

Hi-res audio fraud FAQ.

What fake hi-res actually is, how the FFT detector spots it, and whether anyone can hear the difference.

  1. What is a fake hi-res audio file?

    A file that claims a high sample rate (96 kHz, 192 kHz) or bit depth (24-bit) but actually contains content from a lower-resolution source, typically upsampled from a 44.1 kHz CD master or, worse, a lossy MP3. The container says hi-res; the audio is not. This is widespread in some streaming catalogues.

  2. How does the hi-res fraud detector work?

    It runs an FFT (fast Fourier transform) on your file and plots the actual frequency content. A genuine 96 kHz file shows energy up to 48 kHz; a 192 kHz file up to 96 kHz. A fake hi-res file shows a hard brick-wall cutoff around 20-22 kHz, the giveaway that the audio came from a 44.1 kHz source, regardless of what the container claims.

  3. Can I hear the difference between real and fake hi-res?

    Almost never directly. Human hearing tops out at 20 kHz and falls fast above 16 kHz with age. The case for hi-res is mostly about the master, not the format: real hi-res releases often come from better masters with more dynamic range. The detector tells you whether you are getting the high-rate content you paid for.

  4. Does the file get uploaded to your server?

    No. The FFT analysis happens entirely in your browser using the Web Audio API. The file is decoded into an AudioBuffer locally, analyzed, and discarded when you close the page. We never see your audio files.