Convert WMA to AIF — Free Online Tool
Convert WMA files to AIF format by decoding Microsoft's lossy WMA audio and re-encoding it as uncompressed PCM (pcm_s16be) — Apple's native lossless audio format. This is ideal when you need to work with WMA source audio in macOS audio tools, DAWs, or any workflow that demands an uncompressed, container-agnostic file.
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FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your WMA file here
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Free — no uploads, no signups. Your files never leave your browser.
Settings
Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
WMA files store audio using Microsoft's proprietary lossy WMA codec (typically wmav2), which uses perceptual compression to discard audio data the human ear is less likely to notice. During conversion, FFmpeg fully decodes the compressed WMA bitstream back into raw PCM audio samples, then writes those samples into an AIF container using the pcm_s16be codec — 16-bit, big-endian, signed PCM, which is the standard uncompressed format Apple defined for AIFF. Because WMA is lossy, any audio detail already discarded during the original WMA encoding cannot be recovered; the AIF output will be a lossless representation of what the WMA file contained, not a reconstruction of the original pre-WMA source. File sizes will increase significantly since PCM stores every audio sample without compression.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg program. In the browser-based version of this tool, FFmpeg runs via WebAssembly (FFmpeg.wasm) entirely within your browser — no files leave your device. |
-i input.wma
|
Specifies the input file — a WMA audio file using Microsoft's proprietary ASF container and wmav2 (or wmav1) lossy audio codec. FFmpeg automatically detects the WMA codec from the file headers. |
-c:a pcm_s16be
|
Sets the audio codec for the output to pcm_s16be — 16-bit signed PCM in big-endian byte order. This is the uncompressed audio encoding that Apple defined for the AIFF format, and it is what distinguishes AIF from the little-endian PCM used in WAV files. |
output.aif
|
Defines the output filename and container. The .aif extension tells FFmpeg to wrap the pcm_s16be audio stream in an AIFF container, producing a file natively compatible with macOS, Logic Pro, GarageBand, and other Apple audio environments. |
Common Use Cases
- Importing WMA music purchased or downloaded from older Microsoft services into Logic Pro, GarageBand, or Pro Tools, which work natively with AIF/AIFF files
- Archiving a WMA audio collection in an uncompressed format before the WMA codec becomes less supported, ensuring long-term playback compatibility on macOS
- Preparing WMA voice recordings or field audio for use in Final Cut Pro timelines, which prefer uncompressed AIF for frame-accurate editing
- Converting WMA audiobook chapters into AIF so they can be processed and mastered in audio editing tools that require uncompressed input
- Providing a broadcast or post-production house with uncompressed AIF deliverables sourced from WMA reference files supplied by a client
- Stripping away WMA's proprietary container to work with the decoded audio in academic or forensic audio analysis tools that require raw PCM in a standard container
Frequently Asked Questions
No — converting WMA to AIF does not restore any quality lost during the original WMA encoding. WMA is a lossy codec, meaning it permanently discards audio information to achieve smaller file sizes. The AIF output is a lossless, uncompressed copy of whatever audio the WMA file contains, but it cannot recover detail that was already discarded. Think of it as making a perfect, uncompressed copy of an imperfect original.
WMA compresses audio data — a 128 kbps WMA file is using lossy compression to store audio in a fraction of the space. AIF with pcm_s16be stores every audio sample as raw, uncompressed data. A standard stereo AIF at 16-bit / 44.1 kHz uses roughly 10 MB per minute of audio, regardless of the WMA source bitrate. This size increase is expected and is simply the cost of uncompressed storage.
The default pcm_s16be (16-bit) is appropriate for most WMA sources, since WMA audio is typically mastered and encoded at CD quality (16-bit / 44.1 kHz or 48 kHz). If your WMA source was derived from a high-resolution master and you want to preserve the decoded headroom, you can modify the FFmpeg command to use pcm_s24be for 24-bit output: ffmpeg -i input.wma -c:a pcm_s24be output.aif. However, since WMA is lossy, the extra bit depth will not add real audio quality — it may just result in a larger file.
WMA files often contain rich metadata using the ASF (Advanced Systems Format) container's metadata fields. FFmpeg will attempt to map compatible tags — such as title, artist, and album — to the AIF container's standard metadata chunks. However, WMA-specific metadata fields (especially DRM licensing information or extended Microsoft-proprietary tags) will not carry over to AIF, since AIF has no equivalent container support for those fields.
The single-file FFmpeg command shown on this page can be wrapped in a shell loop for batch processing. On macOS or Linux, use: for f in *.wma; do ffmpeg -i "$f" -c:a pcm_s16be "${f%.wma}.aif"; done. On Windows Command Prompt, use: for %f in (*.wma) do ffmpeg -i "%f" -c:a pcm_s16be "%~nf.aif". This will convert every WMA file in the current directory to a matching AIF file.
No — DRM-protected WMA files (common with older Windows Media Player purchases and subscription services) cannot be converted by FFmpeg or this browser-based tool. FFmpeg does not include DRM decryption capabilities. The WMA format supports DRM via Microsoft's PlayReady system, and protected files will either fail to open or produce silence. You must obtain a DRM-free version of the file before conversion is possible.
Technical Notes
The WMA format uses Microsoft's wmav2 codec by default (an improvement over the original wmav1), which applies psychoacoustic lossy compression similar in concept to MP3 and AAC but using Microsoft's proprietary algorithms. When FFmpeg decodes wmav2 and writes pcm_s16be into an AIF container, the output is a standard AIFF file fully compatible with macOS Finder, iTunes/Music, Logic Pro, and virtually all professional audio software on Apple platforms. The pcm_s16be codec writes 16-bit signed integers in big-endian byte order, which is the byte order defined in Apple's original AIFF specification — distinguishing AIFF from the little-endian WAV format. One important limitation: WMA files encoded with wmav1 (the older codec) are also supported by FFmpeg's decoder, so legacy WMA files will convert correctly without any command changes. DRM-encumbered WMA files are not supported. Because the conversion involves a full decode-then-encode pipeline (not a remux), it is computationally heavier than container-swap operations, and processing time scales with file duration.