Choose the audio
Start with the included example or select an audio file from your device.
This audio spectrogram generator turns an audio file into a visual time-frequency map directly in your browser. Start with the included example or choose your own audio, inspect how frequency energy changes over time, and export the finished spectrogram as a PNG image.
The example audio is ready by default. Replace it with your own compatible audio file whenever you want, choose the analysis resolution, then generate a frequency-over-time visualization.
The selected file is decoded and analyzed locally in your browser.
Choose your audioWaiting for audio analysis
Higher frequencies ↑
A waveform shows amplitude changing over time, but it does not directly show which frequencies create that sound. A spectrogram adds the frequency dimension. Time runs horizontally, frequency runs vertically, and brightness represents the relative strength of frequency content within each analyzed section.
When you generate the image, the browser decodes the audio into PCM sample data. The signal is divided into short overlapping windows. Each window is shaped with a Hann window and analyzed with a Fast Fourier Transform to estimate its frequency content.
The resulting FFT frames are drawn next to one another to create the spectrogram. If you want to experiment with audio from a different perspective, the Interactive Online Audio Mixer lets you explore level relationships, while the Mixer Console Simulator provides another hands-on view of mixing controls.
Sustained tones can form horizontal structures, short events may appear as brief vertical features, and complex material creates combinations of energy distributed across time and frequency.
Listening remains the primary way to understand audio, but a visual representation can reveal relationships that are difficult to locate from a waveform alone. You can inspect where low, mid and high frequency activity occurs and see how that distribution changes through the file.
This can be useful for learning, comparing sections of a recording, examining tonal events, finding short noises, studying harmonic structures or simply understanding how different sounds appear in a time-frequency representation.
When working with recorded instruments, these visual patterns can complement the practical ideas discussed in our instrument recording guide. For a wider introduction to preparing and working through a session, see the First Time Recording Studio Guide.
Start with the included example or select an audio file from your device.
The browser divides the signal into windows and measures frequency content across the recording.
Inspect the generated spectrogram and export the canvas as a PNG image when needed.
An audio spectrogram generator online makes it possible to move from an audio file to a visual frequency map without preparing a separate analysis project. Load the sound, choose an analysis resolution and inspect how its spectrum develops from beginning to end.
Every point in a spectrogram combines three pieces of information: time, frequency and relative spectral magnitude. Reading those dimensions separately makes the image much easier to understand.
FFT size controls how many audio samples are examined in each analysis window. A larger FFT provides finer frequency-bin spacing but spans a longer interval of the signal. A smaller FFT uses a shorter window and therefore follows rapid changes more closely while providing coarser frequency spacing.
There is no single resolution that is ideal for every sound. Try different settings and compare the result. Detailed harmonic material may benefit from a larger transform, while shorter events can be easier to inspect with a smaller analysis window.
A waveform primarily shows signal amplitude against time. Two sections can have similar waveform levels while containing very different frequency distributions. A spectrogram separates that content vertically, making those differences visible.
This makes the two views complementary rather than interchangeable. The waveform is useful for seeing timing and amplitude shape; the spectrogram is useful when the frequency composition itself is important.
If you are learning how these observations connect to broader production decisions, explore Audio Tools for Recording, Mixing, and Ear Training or read about music and musical expression.
Use the audio player below the visualization to connect visible structures with the sounds you hear. Moving between listening and visual inspection is often more informative than treating the spectrogram as an isolated picture.
The tool starts with an example so you can generate a spectrogram immediately. To examine another recording, choose a compatible audio file from your device. The player and analysis source are then switched to that file.
This makes the audio spectrogram tool useful for comparing different sources: vocals, instruments, speech, full mixes, sound effects or other material that your browser can decode.
For additional context around vocal material, you can read how long vocal recording can take or explore the practical workflow described on the vocal and speech recording page.
Voice contains a changing combination of fundamental frequency, harmonics and resonant regions. Consonants, vowels, pauses and transitions create visibly different patterns. A spectrogram can therefore provide another way to examine how a spoken or sung performance develops through time.
Speech-focused projects can also be explored through the voiceover recording overview and the page about Russian voice over for U.S. projects.
Instrument recordings can contain fundamentals, harmonics, transients, resonances and broadband components in very different proportions. A full mix combines many such sources, so its spectrogram can become considerably denser.
Instead of trying to identify every visible feature, begin with broad questions. Where is most of the energy concentrated? Which frequency regions remain active for long periods? Where do sudden broadband events occur? How does the pattern change between quieter and denser sections?
Musicians interested in different recording approaches can continue with the overview of recording across music genres or the more focused discussion of blues and country recording.
As a visualizer, a spectrogram differs from a decorative animation that simply reacts to loudness. The image is calculated from frequency analysis of the decoded signal. Each vertical slice represents spectral information from a particular part of the recording.
This makes it suitable for inspection and learning as well as visualization. You can change FFT size, regenerate the image and observe how analysis resolution changes the way short events and narrow frequency components are represented.
The frequency-range control changes the highest frequency shown in the image. Reducing the displayed range gives more vertical space to lower frequencies, which can be useful when the material you want to inspect is concentrated there.
The actual highest analyzable frequency is also limited by half of the decoded audio's sample rate. If a selected display range exceeds that limit, the generator automatically uses the available frequency range.
After analysis is complete, the generated canvas can be exported as a PNG. The exported image contains the spectrogram together with basic time and frequency labels, making it easier to keep a visual reference or compare it with another analysis.
The export is created from the generated canvas in the browser. You do not need to convert the original audio into an image file manually.
The selected audio is read by browser APIs and decoded for analysis on the device. The FFT calculations, drawing and PNG creation in this tool all happen client-side. A file selected through this page is not sent to a processing endpoint by the code below.
If you are interested in how audio work develops beyond analysis tools, the Audio Content Recording Services overview covers several kinds of recorded material, while Musician Psychology and Recording Confidence looks at the human side of performing and recording.
Continue with practical tools and guides covering audio production, recording and working with sound.
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