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Free Audio Noise Reducer

Remove background noise from audio, fully private|
4.7 (640)

A free, private audio noise reducer that removes background noise from voice recordings without uploading anything. It is built on RNNoise, the open-source noise-suppression model from Xiph.Org (the makers of Opus and Vorbis), compiled to WebAssembly so it runs entirely in your browser. RNNoise combines classic digital signal processing with a small recurrent neural network trained to tell speech from noise, and it works on 48kHz audio in real time. Upload an MP3, WAV, or M4A recording and the tool decodes it, resamples it to 48kHz mono, runs every frame through RNNoise, and gives you a cleaned file to preview and download as WAV or MP3. Because the model is tiny and runs on your own device, your recording is never uploaded, logged, or stored, which makes it safe for private interviews, calls, and voice memos. Nothing leaves the browser.

Remove background noise from audio without uploading it

Most online noise removers upload your recording to a server, run it through a hosted model, and send a cleaned file back, which means your audio leaves your control and often sits behind a subscription or a daily limit. This free noise reducer works the other way around: the RNNoise model runs inside your browser tab. Your recording is decoded and cleaned on your own device, so the interview, call, or voice memo you upload never touches a server.

That makes it a strong fit for private and confidential audio, from client interviews to personal voice notes, where sending a recording to a third-party service is not acceptable. You still get a clear before-and-after comparison and a downloadable WAV or MP3, and you can confirm nothing is uploaded by watching the Network tab in your browser DevTools while it works.

Powered by Xiph RNNoise, running in your browser

This tool is built on RNNoise, the open-source noise-suppression library from Xiph.Org, the organization that created the Opus and Vorbis audio codecs. RNNoise is notable because it does not rely on a huge neural network. Instead it combines classic digital signal processing, which splits the sound into frequency bands, with a small recurrent neural network that decides how much of each band is speech versus noise. That design keeps the model only a few hundred kilobytes and fast enough to run in real time.

Here RNNoise is compiled to WebAssembly and embedded directly in the page, so there is no separate model download and processing starts immediately. The audio is resampled to the 48kHz sample rate RNNoise expects, downmixed to mono, and passed through the model one short frame at a time, then re-encoded to WAV or MP3 in the browser. RNNoise is released under a permissive BSD license.

Getting the best results and where it fits

RNNoise was trained to protect speech, so it shines on voice recordings with steady background noise: fan or air-conditioner hum, room tone, and hiss all get pulled down while the voice stays intact. It is less suited to music, where reducing "noise" can also dull instruments, and to very loud or sudden noises that overlap the voice, which it can only partly suppress. Setting realistic expectations helps: think of it as a strong cleanup pass, not a magic restore button.

A practical workflow is to clean a recording here first, then use the result elsewhere. Feeding denoised audio into a transcription or subtitle tool often improves accuracy, because the recognizer gets a cleaner voice signal. Export lossless WAV if you plan to edit further, or MP3 at 192 kbps or higher for a smaller file to share. For long recordings, a desktop browser will process faster than a phone, since every frame is handled on your own CPU.

How It Works

1

Choose your output format (WAV for lossless, or MP3 with a bitrate), then upload a noisy audio file: nothing is sent to a server.

2

The tool decodes the audio, resamples it to 48kHz mono, and runs every frame through the RNNoise neural network in your browser.

3

Compare the original and cleaned audio with the built-in players, then download the denoised file as WAV or MP3.

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Key Features

Powered by RNNoise, the open-source noise-suppression library from Xiph.Org, the same organization behind the Opus and Vorbis codecs
Uses a hybrid of classic signal processing and a compact recurrent neural network trained to separate speech from noise
Runs entirely in your browser via WebAssembly, with the model weights inlined so there is no separate download and it starts instantly
Removes steady background noise such as fan hum, air conditioning, hiss, and room tone, and reduces many transient noises
Accepts common audio formats (MP3, WAV, M4A, FLAC, OGG, WebM) and decodes them with the browser Web Audio API
Exports the cleaned audio as lossless WAV or as MP3 at 128, 192, 256, or 320 kbps
Side-by-side original and cleaned players so you can hear the difference before downloading
No signup, no API keys, no server calls, and no rate limits: clean as many files as you want for free
No upload and no file-size cap imposed by a server, unlike most online noise removers
Released under a permissive BSD license, the same open-source license as RNNoise itself

Privacy & Trust

Your audio never leaves the browser: decoding and noise reduction run entirely on your device via WebAssembly with zero upload
No audio is uploaded, logged, stored, or transmitted to any server at any point
No tracking or analytics of the files you clean or the results produced
Built on open-source RNNoise from Xiph.Org (BSD license) with the model compiled into the page, not fetched from a third party
Verify privacy yourself by checking the Network tab in your browser DevTools while cleaning audio: you will see no requests carrying your file

Use Cases

1Clean up voice memos, interviews, and podcast recordings before editing or publishing
2Reduce fan, air-conditioner, or background hum on video-call and meeting recordings
3Improve the clarity of narration or voiceover captured in a noisy room
4Remove steady hiss from old or low-quality recordings
5Prepare clearer audio before running it through transcription or subtitle tools
6Denoise sensitive or confidential recordings that cannot be uploaded to a cloud service

Limitations

  • RNNoise is designed for speech, so it works best on voice recordings and may not suit music, where it can dull instruments
  • It targets steady background noise well, but very loud, sudden, or overlapping noises may only be partly reduced
  • Audio is processed as 48kHz mono, so a stereo file is downmixed to a single channel in the output
  • Very long files take longer to process because every 10-millisecond frame is run through the model on your CPU
  • The browser Web Audio API decodes most common formats, but an unusual container or codec may need converting to MP3 or WAV first

Q&A SESSION

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Frequently Asked Questions

Is this noise reducer really free?

Yes, it is completely free with no signup, no account, and no usage limits. Because RNNoise runs on your own device through WebAssembly instead of a paid cloud service, there are no per-file costs to pass on. Many online noise removers and desktop apps such as Krisp or Adobe Podcast Enhance are subscription based or cap free usage, while this tool lets you clean as many files as you want for free.

Is my audio uploaded to a server?

No. The entire process, decoding the audio and running RNNoise, happens locally in your browser using WebAssembly. Your recording is processed on your own device with zero network requests carrying it. Nothing is uploaded, logged, or stored, which makes this safe for private interviews, calls, and voice memos. You can confirm this by opening the Network tab in your browser DevTools while you clean a file and seeing no upload.

What is RNNoise?

RNNoise is an open-source noise-suppression library created by Jean-Marc Valin at Xiph.Org, the organization behind the Opus and Vorbis audio codecs. It combines traditional digital signal processing with a small recurrent neural network (a gated recurrent unit) trained on many hours of speech and noise. This hybrid design keeps the model tiny and fast enough to run in real time, which is why it can run in a browser tab, while still being effective at telling voice apart from background noise.

What kinds of noise can it remove?

It is strongest on steady, continuous background noise such as fan and air-conditioner hum, computer and room tone, tape or electronic hiss, and general ambient noise behind a voice. It also reduces many everyday transient noises. It is less effective on very loud, sudden, or speech-like noises, and on music, since the model was trained specifically to preserve speech. For voice recordings it typically gives a clear, noticeable improvement.

Do I need to install anything?

No installation is needed. It is a pure web tool that runs in any modern browser. Unlike RNNoise itself, which is normally a C library you compile, here it is already compiled to WebAssembly and embedded in the page, so there is nothing to download or set up. There is no extension, no desktop app, and no command line involved.

How does this compare to Krisp or Adobe Podcast Enhance?

Krisp and Adobe Podcast Enhance are cloud services: Krisp is a subscription app that processes your microphone in real time, and Adobe Podcast Enhance uploads your file to Adobe servers to clean it. Both can produce excellent results, but they involve accounts, limits, and sending your audio to a company. This tool trades a little of that polish for complete privacy and no cost: it uses the open-source RNNoise model, runs on your device, and never uploads anything.

Why is the output mono, and can I keep stereo?

RNNoise processes a single channel of 48kHz audio, so this tool downmixes a stereo file to mono before cleaning it, and the output is mono. For voice recordings, which are usually mono anyway, this is not a drawback. If you specifically need to keep stereo, you would need a tool that runs the model on each channel separately, which is outside the scope of this simple cleaner.

What output formats and quality can I get?

You can export the cleaned audio as a lossless WAV file, which preserves the exact processed samples, or as an MP3 at 128, 192, 256, or 320 kbps if you want a smaller file. WAV is the best choice if you plan to edit the audio further, while MP3 at 192 kbps or higher is a good balance of quality and size for sharing or listening.

Is there a file-size or length limit?

There is no server-imposed limit, since everything runs in your browser. The practical limit is your device memory, because the audio is decoded and held in memory while it is processed. Short clips and typical podcast-length recordings work comfortably, while very long files use more memory and take longer, as each 10-millisecond frame is processed one at a time on your CPU.

Does it work offline and on mobile?

Because the model is embedded in the page and everything runs on-device, once the page has loaded it can process audio without an active internet connection. It also works on mobile browsers, though phones are slower than a laptop or desktop, so long files will take more time. For the best experience with longer recordings, use a desktop browser.

Can I use the cleaned audio before transcription?

Yes, and it is a great use case. Removing steady background noise first often improves the accuracy of speech-to-text and subtitle tools, because the recognizer has a cleaner voice signal to work with. You can clean a recording here, download the WAV, and then run it through a transcription or subtitle generator for better results.

Will it make studio-quality audio out of a bad recording?

No tool can fully recover audio that was badly recorded, but noise reduction can meaningfully improve clarity by pulling the voice out from under steady background noise. RNNoise is good at that specific job. For the best final result, combine a clean recording environment, this noise reducer, and light editing rather than relying on any single step to fix everything.