Spectrogram

See sound as a picture: time runs left to right, pitch goes up, and brighter means louder. Use the microphone live or open a file.

How to make a spectrogram online

Three steps, in your browser

Choose the microphone or a file

Press Use the microphone and allow it, or open an audio or video file (MP3, WAV, FLAC, M4A, MP4…) up to 2 GB.

Read the picture

Time runs left to right and frequency bottom to top. Point at any spot to see the time, the frequency and the loudest note there.

Change the view and save it

Switch between a logarithmic and a linear axis, show up to 5, 11 or 22 kHz, and save the picture as a PNG with its axes.

How to read a spectrogram

Each column is a moment of the sound split into frequencies. Here is what the common shapes mean.

What you see	What it means
A thin horizontal line	A steady tone: a whistle, a held note, a hum. Its height is its pitch.
Several evenly spaced lines stacked above each other	One note with its harmonics, as from a voice or an instrument. The lowest line is the note you hear.
A short vertical stripe	A click, a clap or a drum hit: a burst of energy at many frequencies at once.
A line that bends up or down	A pitch that changes: a slide, vibrato, a siren or birdsong.
A bright band at the bottom	Bass and kick drum, or low rumble such as traffic or wind.
An even haze across the whole height	Noise: hiss, rain, a fan, or a cymbal.
Everything stops at a sharp ceiling around 16 kHz	The file was compressed (for example MP3 at 128 kbps) at some point, even if it is now a WAV or FLAC.

What this spectrogram does

Live from the microphone

The picture scrolls as you speak, sing or play, with the loudest frequency and its note name. Voice processing is off, so nothing is filtered out.

Any audio or video file

MP3, WAV, FLAC, M4A, OGG and the sound of MP4 or MOV videos, up to 2 GB. The first 6 minutes are drawn.

Full range up to kHz

Files are read at 44.1 kHz, so you see everything a person can hear, including the high end where compression leaves its mark.

Logarithmic or linear axis

The logarithmic axis spreads notes evenly, like a piano. The linear axis gives the treble room, for checking cut-offs and noise.

Read any point, play from it

Point at the picture for the time, frequency and loudest note there, and click to play the file from that moment.

Private and free

Nothing is uploaded and nothing is recorded: the sound is analysed on your device. No sign-up, no watermark on the PNG.

Spectrogram FAQ

What a spectrogram shows and how to use this one

What is a spectrogram?

A spectrogram is a picture of sound. Time runs from left to right, frequency from bottom (low) to top (high), and the brightness of each point shows how loud that frequency is at that moment. It shows what a waveform cannot: which notes, harmonics and noises make up the sound.

How do I see a spectrogram of my voice?

Press Use the microphone and allow access. Speak or sing: your voice appears as a stack of lines, the lowest one being your pitch. The note name of the loudest frequency is shown under the picture. Nothing is recorded.

How do I make a spectrogram of an MP3 or other audio file?

Open the file with the box on this page. It is decoded on your device and drawn in a few seconds. MP3, WAV, FLAC, M4A, OGG and the audio of videos all work, up to 2 GB; the first 6 minutes are drawn.

Can a spectrogram show whether a FLAC or WAV is really lossless?

Often, yes. Choose the linear axis and show up to 22 kHz. A file that was once an MP3 or AAC usually stops at a sharp ceiling around 16 kHz (128 kbps) or 19–20 kHz (320 kbps), across the whole song. A true CD-quality file has content fading out towards 22 kHz. A ceiling alone is not proof: some recordings simply have little treble.

What is the difference between the logarithmic and the linear axis?

On the logarithmic axis every octave takes the same height, the way we hear pitch, so melodies and bass notes are easy to follow. On the linear axis every kilohertz takes the same height, which gives most of the picture to the treble: better for noise, cut-offs and high sounds.

Is this the same as a spectrum analyzer?

A spectrum analyzer shows the frequencies of one moment as a curve. A spectrogram shows the same thing for every moment, side by side, so you see how the sound changes over time. The loudest frequency under the picture is what a spectrum analyzer's peak would read.

Is my audio uploaded or recorded?

No. The microphone feeds the picture directly and is never recorded, and files are read by your browser on your device. Nothing is sent to our servers.

Can I save the spectrogram as an image?

Yes. Press Save as PNG to download the picture with its frequency axis, and for a file the time axis too. It has no watermark.