Can I really convert FLAC to MP3 without uploading the file?

Yes. FLAC to MP3 runs entirely in your browser on hushvert using an in-browser build of ffmpeg, so the FLAC file never leaves your device. You can confirm it by turning on airplane mode before converting, or by watching your browser's Network tab and seeing that no file bytes are uploaded. Note that MP3 is a lossy format, so the audio is genuinely re-encoded rather than copied sample-for-sample. If you want to keep every sample, convert FLAC to WAV instead.

How do I extract audio from a video without uploading the video?

Drop the video onto hushvert and convert it to MP3. Extracting an MP3 audio track from MP4, MOV, MKV, WebM, or AVI runs client-side in your browser, so the video is never uploaded. The audio stream is demuxed and re-encoded locally. Because the output is audio, the 200 MB per-file ceiling applies. Files larger than that would need the separate, clearly-labeled server lane.

Is converting audio in the browser worse quality than an online server converter?

No. The same ffmpeg engine logic runs whether it executes on a remote server or in your browser via WebAssembly, so quality is equivalent. Lossless-to-lossless conversions like WAV to FLAC preserve audio samples exactly. Any conversion to a lossy target like MP3 or OGG re-encodes the audio, which is true of every MP3 encoder regardless of where it runs.

Is there a file size limit for no-upload audio conversion?

Yes. Client-side audio conversion, including extracting audio from video, has a 200 MB per-file ceiling. That covers most MP3, M4A, FLAC, OGG, and typical WAV files, though a very long uncompressed WAV recording can exceed it. The limit exists so the in-browser engine stays fast and safe on lower-RAM devices.

Does hushvert keep or see my audio files?

No. For the audio conversions on this page, your files never reach any hushvert server, so there is nothing for us to keep or see. The conversion happens on your own device. You can verify the no-upload behavior in airplane mode or in the browser Network tab, and the engine is open source under the MIT license so the behavior is auditable.

Do I need an account or a subscription to convert audio here?

No. All client-side audio conversions are unlimited and free, with no account and no subscription required. Accounts and paid credits exist only for the separate server lane used by tasks a browser cannot do, and those credits never expire. The browser-based audio conversions on this page never touch that lane.

Audio converter without uploading: MP3, WAV, FLAC, OGG, M4A

Why "without uploading" actually matters for audio

Most online audio converters work the same way under the hood: you pick a file, your browser uploads the raw bytes to the company's server, the server runs the conversion, and you download the result. That means a full copy of your recording, voice memo, interview, or music lives on someone else's machine, even if only briefly. In March 2025 the FBI publicly warned that free online file-converter sites are a common vector for malware and data theft, precisely because so many of them route your files through servers you cannot see.

Audio is often more sensitive than people assume. A WAV from a therapy session, a FLAC master of unreleased music, a voice memo with a phone number in it, an M4A of a confidential call recording: once uploaded, you are trusting a stranger's retention policy, security, and good faith. hushvert removes that trust requirement for audio entirely. For every format pair on this page, the conversion happens locally in your browser tab. There is no upload to opt out of because there is no upload at all.

How browser-based audio conversion works (and how you can prove it)

When you drop an audio file onto hushvert, your browser downloads a WebAssembly build of the ffmpeg conversion engine once, then runs that engine on your file inside the page. The decoding and re-encoding happen on your own CPU. The output is written back to a download in your browser. At no point does the audio data travel over the network.

You do not have to take our word for it, and you should not. Two checks prove it in under a minute. First, the airplane-mode test: load the converter, switch your device to airplane mode (or just pull the network cable), and convert a file. It still works, because there is nothing to upload. The /privacy-proof page includes a built-in airplane-mode demo that does exactly this. Second, the Network tab: open your browser's developer tools, switch to the Network tab, and convert. You will see the engine load, then no upload of your file bytes. This is verifiable no-upload conversion, and it is the core reason hushvert exists.

The audio formats you can convert in the browser

hushvert handles roughly 18 client-side audio conversions today, all running on the same in-browser ffmpeg engine. The most common ones each have their own dedicated page: FLAC to MP3, FLAC to WAV, WAV to MP3, MP3 to WAV, M4A to MP3, M4A to WAV, OGG to MP3, MP3 to OGG, MP3 to M4A, WAV to FLAC, AAC to MP3, AIFF to MP3, and WMA to MP3.

A point worth being precise about: not every conversion is the same kind of operation. When you convert between lossless formats (for example WAV to FLAC, or FLAC to WAV), the audio samples are preserved exactly, with no generational quality loss. When your target is a lossy format like MP3, OGG, or AAC, the audio is genuinely re-encoded, which means it is recompressed rather than copied sample-for-sample. That is true of every MP3 encoder everywhere, not a hushvert limitation, but we would rather you know it than discover it. If your goal is to archive a master without losing anything, convert to a lossless target like WAV or FLAC. If your goal is a small, universally playable file, MP3 or M4A is the right tradeoff.

Extract audio from a video, also without uploading

One of the most-searched no-upload tasks is pulling the audio track out of a video, and it runs entirely in your browser here too. hushvert can extract an MP3 audio track from MP4, MOV, MKV, WebM, and AVI video files, all client-side. The video never uploads; the engine demuxes the audio stream and re-encodes it to MP3 locally.

This is genuinely useful when you have a lecture, podcast recording, interview, or screen capture and you only need the sound. Because audio extraction produces an audio output, it uses the same 200 MB per-file ceiling as the rest of the audio lane, not the smaller limit that applies to re-encoding a full video. If you have a multi-gigabyte video file that exceeds the browser ceiling, that specific job would need the clearly-labeled server lane, and hushvert tells you before you start whenever a conversion leaves your device. For audio extraction within the limit, nothing uploads.

The honest limits

Browser-based conversion is the right default for audio, but it has real edges and we will name them. The per-file ceiling for client-side audio is 200 MB. That comfortably covers full-length WAV and FLAC files in most cases, but a very long uncompressed WAV recording can exceed it. The engine runs on your device's CPU, so a large file on an older phone is slower than the same file on a modern laptop, because the work is happening locally rather than on a fast remote server.

There is also a one-time cost: the first conversion in a session downloads the WebAssembly engine, which is the price of keeping your files off any server. After that it is cached. Finally, the no-upload guarantee on this page covers the audio and audio-from-video conversions listed here, which run client-side. hushvert does operate a separate, clearly-labeled server lane for tasks a browser genuinely cannot do, such as office documents to PDF and very large video, and that lane is always marked "this one leaves your device" before you begin, with server inputs deleted immediately and outputs within about an hour. None of the audio conversions on this page use it.

How hushvert compares to other audio converters

To be fair about the alternatives: established desktop and command-line tools like ffmpeg, Audacity, and dBpoweramp are excellent, fully offline, and handle formats and batch jobs beyond what any web converter does. If you convert audio constantly, installing a real desktop tool is a legitimate choice and we will not pretend otherwise. The tradeoff is installation, a learning curve, and platform-specific setup.

Among web-based converters, the convenient ones are server-based: they upload your file to do the work, and that is the structural difference. hushvert's audio conversions run in your browser with no upload, which you can verify, and they are unlimited and free with no account required. There is no subscription, and any paid credits, used only for the separate server lane and never for these browser-based audio conversions, never expire. The conversion engine is also open source under the MIT license, published as @hushvert/engine, so the no-upload behavior is auditable rather than just asserted.

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Common questions

Can I really convert FLAC to MP3 without uploading the file?: Yes. FLAC to MP3 runs entirely in your browser on hushvert using an in-browser build of ffmpeg, so the FLAC file never leaves your device. You can confirm it by turning on airplane mode before converting, or by watching your browser's Network tab and seeing that no file bytes are uploaded. Note that MP3 is a lossy format, so the audio is genuinely re-encoded rather than copied sample-for-sample. If you want to keep every sample, convert FLAC to WAV instead.
How do I extract audio from a video without uploading the video?: Drop the video onto hushvert and convert it to MP3. Extracting an MP3 audio track from MP4, MOV, MKV, WebM, or AVI runs client-side in your browser, so the video is never uploaded. The audio stream is demuxed and re-encoded locally. Because the output is audio, the 200 MB per-file ceiling applies. Files larger than that would need the separate, clearly-labeled server lane.
Is converting audio in the browser worse quality than an online server converter?: No. The same ffmpeg engine logic runs whether it executes on a remote server or in your browser via WebAssembly, so quality is equivalent. Lossless-to-lossless conversions like WAV to FLAC preserve audio samples exactly. Any conversion to a lossy target like MP3 or OGG re-encodes the audio, which is true of every MP3 encoder regardless of where it runs.
Is there a file size limit for no-upload audio conversion?: Yes. Client-side audio conversion, including extracting audio from video, has a 200 MB per-file ceiling. That covers most MP3, M4A, FLAC, OGG, and typical WAV files, though a very long uncompressed WAV recording can exceed it. The limit exists so the in-browser engine stays fast and safe on lower-RAM devices.
Does hushvert keep or see my audio files?: No. For the audio conversions on this page, your files never reach any hushvert server, so there is nothing for us to keep or see. The conversion happens on your own device. You can verify the no-upload behavior in airplane mode or in the browser Network tab, and the engine is open source under the MIT license so the behavior is auditable.
Do I need an account or a subscription to convert audio here?: No. All client-side audio conversions are unlimited and free, with no account and no subscription required. Accounts and paid credits exist only for the separate server lane used by tasks a browser cannot do, and those credits never expire. The browser-based audio conversions on this page never touch that lane.

Convert audio without uploading: MP3, WAV, FLAC, OGG, M4A, and more