Audio File Inspector Online Free — Metadata & Spectrogram

A free audio authenticity checker that detects fake lossless and transcoded files. Verifies true encoding quality by analyzing the frequency spectrum — works entirely in your browser.

How to Inspect an Audio File

Upload or drag-and-drop any audio file (MP3, WAV, FLAC, OGG, AAC, M4A, AIFF, WebM, Opus)

Basic info, metadata, and tags appear instantly

Expand sections for deep analysis — technical metrics, spectrogram, stereo field, forensics

Export the full report as JSON for documentation or further analysis

Inspect any audio file at forensic level — detect fake lossless, check bitrate and quality

Process

Drop your audio file here or browse

MP3, WAV, OGG, FLAC, AAC, M4A, M4B, WMA, AIFF, OPUS, CAF, MP4, WEBM, MOV, MKV, AVI, WMV, FLV, M4V, 3GP, TS, MTS, M2TS, VOB, MPG, MPEG, OGV ·

File Identity

File name—

File size—

MIME type—

Extension—

Detected format—

SHA-256 (file)—

Audio Properties

Duration—

Sample rate—

Channels—

Bit depth—

Bitrate—

Codec—

Encoder—

Metadata & Tags

Tag	Value

Quality Score

0—

Estimated original bitrate—

Quality factors

Technical Analysis

Peak level—

RMS level—

Dynamic range—

Loudness (LUFS)—

True peak—

DC offset—

Clipping—

Leading silence—

Trailing silence—

Zero crossing rate—

Peak count (>-1 dB)—

Noise floor—

Signal-to-noise ratio (SNR)—

Headroom—

Amplitude histogram

Loudness & Streaming

Integrated loudness—

Short-term max—

Momentary max—

Loudness range (LRA)—

True peak—

EBU R128—

ReplayGain—

Loudness penalty

Platform	Target	Adjustment

Frequency Analysis

Frequency spectrum

Spectrogram

Dominant frequencies—

Effective bandwidth—

Spectral cutoff—

Spectral centroid—

Spectral flatness—

Spectral rolloff (85%)—

Subsonic content (<20 Hz)—

Ultrasonic content (>20 kHz)—

Mel-spectrogram

Stereo Analysis

L/R Balance—

Phase correlation—

Stereo width—

Mid/Side ratio—

Phase meter

—

-10+1

Stereo field (Lissajous)

Stereo difference

Rhythm & Tonality

Tempo (BPM)—

Musical key—

Chromagram

Forensics

Recording / encoding software—

Recording device—

Creation date—

GPS location—

Encoding assessment—

Effective bit depth—

Bit-perfect check—

Data entropy—

Audio fingerprint (PCM SHA-256)—

Sample values

First samples

—

Last samples

—

Forensic data is extracted from file metadata and spectral patterns. Not all files contain this information.

Visualizations

Waveform

Loudness over time

Loudness heatmap

Audio X-Ray

Key findings

Features

Forensic metadata and ID3 tag extraction LUFS loudness and clipping detection Spectrogram and fake-lossless identification Export reports for analysis or sharing

Why Use Our Audio Inspector

Whether you're a music producer checking masters, an audio forensics analyst examining evidence, a podcaster optimizing recordings, or just curious about what's inside your audio files — this inspector gives you the deepest possible look. No registration, no file-size limits, completely free.

Frequently Asked Questions

What audio formats are supported?

MP3, WAV, FLAC, OGG, AAC, M4A, AIFF, WebM, Opus, and WMA. The inspector reads raw binary data, so even partially corrupted files may yield useful information.

Can it detect if an audio file was re-encoded?

Yes. The inspector analyzes the frequency spectrum for sharp cutoffs typical of lossy encoding. If a WAV or FLAC file shows a cutoff around 16-20 kHz, it was likely converted from a lossy source like MP3. Use our audio converter to re-encode in the correct format.

What is the audio fingerprint?

The inspector generates two SHA-256 hashes: one for the raw file bytes (file identity) and one for the decoded PCM audio data (audio fingerprint). The audio fingerprint stays the same even if metadata changes.

What does the spectrogram show?

The spectrogram is a time-frequency visualization showing how audio energy is distributed across frequencies over time. Bright areas indicate high energy. It reveals patterns invisible in a simple waveform view.

💡 Want us to improve this tool just for you?

We can — and it's free! Just send us a quick message with your idea. If you'd like to discuss it in detail, leave your email and we'll get back to you. You can stay anonymous.

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Who is this tool for?

Published 17 Feb 2026 Updated 22 May 2026