Turn WMV files into FLAC in a couple of clicks. WMV is Microsoft's legacy streaming container; FLAC is losslessly compressed audio — CD quality at roughly half the size. Some detail is discarded to fit the target format; how much depends on the format and your settings.
Drop your files here
WMV files (.wmv, .asf) · up to 512 MB each
or paste files from your clipboard
Ready when you are
Drop a WMV file above and FileTools360 will turn it into FLAC — right here on your device, without uploading anything.
Drag them onto the drop area, choose them from your device, or paste them from your clipboard. You can queue several at once. Nothing is sent anywhere — the file stays on this device.
The defaults suit most people. Open Advanced to control bitrate, sample rate and channels.
Press Convert. Everything happens on your own device — nothing is uploaded. Download files one by one, or grab them all as a ZIP.
Privacy, in plain words
What “uploaded” normally means. On most online converters, pressing the button copies your file across the internet onto a computer owned by that website. That copy is what the word “upload” means, and it is the part nobody explains.
What happens instead. This site does not do it. There is no server here that receives files, so your WMV file is read, converted and handed back by the browser you are using right now. It never travels — so there is no copy to store, read, leak or hand over.
Check it yourself in ten seconds
Turn off your Wi-Fi after this page has loaded, then convert a file anyway. It still works, because everything needed is already on your device.
The longer explanation of how this works, and the full detail of what is and is not stored on the privacy page.
Video is the format where the thing being converted is usually a recording of people, and often of people who did not expect a third party to have a copy. It matters more than it sounds, because of what video files usually are:
Medical or therapy consultations
clinical recordings under strict handling rules
Unreleased footage
material under embargo or still being edited
Recorded meetings and calls
everything said, by everyone in the room
Interviews
sources and participants who consented to you, not to a website
A file that is never sent cannot be kept, leaked, subpoenaed or used to train anything. That is a property of how this works, not a promise about how carefully it is run.
WMV is Microsoft's Windows Media video container, tied to Windows Media Player and rarely supported elsewhere.
FLAC compresses audio losslessly, typically to about half the size of WAV. Decompressed, it is bit-for-bit identical to the original — the compression is mathematical, not perceptual.
The two formats solve different problems, which is why converting between them involves trade-offs rather than a straight upgrade.
| Property | Source | Target |
|---|---|---|
| Compression | Container (depends on codec) | Lossless |
| Animation | Yes | — |
| Introduced | 1999 | 2001 |
| Browser support | Windows only, and shrinking. | Great on desktop and Android; iOS support is newer. |
This is not really a format swap — it is extraction. A WMV file carries a video track and an audio track side by side, and converting to FLAC discards the picture and keeps the sound. People do it to turn a lecture, interview, podcast recording or music video into something they can listen to without the video, at a fraction of the file size.
FLAC compresses without discarding data, but it cannot represent everything a WMV file holds. What does not fit is discarded permanently, so converting the result back will not restore it. Keep the WMV original if it is the only copy.
On every sample measured, the FLAC came out smaller — 1.6× smaller at worst and 4.0× smaller at best.
| Sample | WMV in | FLAC out | Change |
|---|---|---|---|
| An easy clipThe compressible end of the range — a clean tone, or a moving test pattern — where a codec does its best work. | 160 KB | 98.5 KB | −39% |
| A hard clipThe other end — pink noise, or dense video grain. Close to incompressible by design, and the worst case for every codec. | 982 KB | 243 KB | −75% |
Produced by this site's own converter. The same code that runs in your browser, at the same default settings, so these are the bytes you would download.
Samples are generated from a fixed seed rather than taken from real photographs or documents, so the corpus is reproducible and carries no licensing question — and so the numbers predict the shape of your result rather than its exact size. Measured 2026-10-01. The method, and the command that regenerates every figure on this page, are on the how it works page.
Source
Microsoft's legacy streaming container.
Target
Lossless compression — CD quality at roughly half the size.
The soundtrack is decoded and re-encoded. Quality is limited by whatever the video already contained — extracting to FLAC cannot add detail back.
Good to know
Runs entirely in your browser
527 converters and tools65 file formatsnothing ever uploaded.