Does converting WMA to AAC lose quality?

Potentially yes. If the source WMA is already lossy (WMA Standard), transcoding to AAC involves a second round of lossy compression, which can cause slight quality degradation. At 256 kbps AAC, the difference is usually inaudible for music. For archival purposes, convert from WMA Lossless or keep the WMA original if you do not need AAC compatibility.

What bitrate should I choose for WMA to AAC?

128 kbps AAC is adequate for casual listening on earbuds or laptop speakers. 192 kbps is a good general-purpose choice that balances quality and file size. 256 kbps is recommended for music where fidelity matters. AAC is more efficient than MP3, so 128 kbps AAC sounds roughly equivalent to 160–192 kbps MP3.

What is the FFmpeg command for WMA to AAC?

The basic command is: ffmpeg -i input.wma -c:a aac -b:a 192k -map_metadata 0 output.m4a. Replace 192k with your chosen bitrate. The -c:a aac flag selects the native AAC encoder, and -map_metadata 0 copies tags (artist, title, album) from the WMA file into the M4A container.

Is my WMA file uploaded anywhere?

No. The metadata inspector uses the Web Audio API entirely in your browser. Your file is read into browser memory only and is never transmitted to any server. Refreshing the page clears all data.

What is the difference between AAC and M4A?

AAC refers to the audio codec (Advanced Audio Coding). M4A is a file container (a subset of the MPEG-4 container) that typically holds AAC-encoded audio. When you convert WMA to AAC using FFmpeg with the .m4a extension, you get an M4A file with AAC audio inside — these terms are often used interchangeably.

Can I convert multiple WMA files at once?

Yes, using a shell loop. On Linux/macOS: for f in *.wma; do ffmpeg -i "$f" -c:a aac -b:a 192k -map_metadata 0 "${f%.wma}.m4a"; done. On Windows PowerShell: Get-ChildItem *.wma | ForEach-Object { ffmpeg -i $_.FullName -c:a aac -b:a 192k -map_metadata 0 ($_.BaseName + ".m4a") }

What is the difference between WMA Standard and WMA Lossless?

WMA Standard is a lossy codec similar to MP3 or AAC — it permanently discards audio data to reduce file size. WMA Lossless is a lossless codec that preserves every bit of the original audio, similar to FLAC. If you have a WMA Lossless source, converting it to 256 kbps AAC produces excellent quality with no perceptible loss.

Does FFmpeg support WMA decoding?

Yes. FFmpeg includes built-in WMA decoders (wmav1, wmav2, wmalossless, wmapro) and does not require any additional codec installation. Simply install FFmpeg from ffmpeg.org and run the command — WMA input is supported out of the box on all platforms.

WMA to AAC Converter

Name: WMA to AAC Converter
Availability: InStock
Author: Nham Vu

Inspect your WMA file metadata in the browser and generate the perfect FFmpeg command to convert it to AAC at your chosen bitrate — no upload required.

Inspect WMA Metadata

Drop a WMA (or any audio) file to read its properties. Nothing is uploaded.

Drop WMA file here or click to browse WMA, MP3, FLAC, WAV, OGG accepted

FFmpeg Command Generator

AAC Bitrate

Copy metadata tags from source (-map_metadata 0)

ffmpeg -i input.wma -c:a aac -b:a 192k -map_metadata 0 output.m4a

Install FFmpeg free at ffmpeg.org. Replace input.wma with your actual filename.

Batch convert (Linux / macOS)

for f in *.wma; do ffmpeg -i "$f" -c:a aac -b:a 192k -map_metadata 0 "${f%.wma}.m4a"; done

Batch convert (Windows PowerShell)

Get-ChildItem *.wma | ForEach-Object { ffmpeg -i $_.FullName -c:a aac -b:a 192k -map_metadata 0 ($_.BaseName + ".m4a") }

GUI alternatives

VLC Media Player — free, cross-platform; use Media > Convert/Save to output AAC/M4A
fre:ac — free, open-source, Windows / macOS / Linux, supports WMA input and AAC output via FDK-AAC
iTunes / Apple Music — on Windows or macOS, import WMA and re-export as AAC using File > Convert > Create AAC Version
dBpoweramp — paid, Windows / macOS, batch WMA-to-AAC with DSP processing and metadata preservation

Drop a WMA file on the left to inspect its metadata

No file is uploaded — everything runs in your browser

AAC Bitrate Reference

Bitrate	Quality	Size / min	Best For
96 kbps	Acceptable	~0.7 MB	Spoken word, podcasts
128 kbps	Good	~0.9 MB	Casual music listening
192 kbps	High	~1.4 MB	General music, streaming prep
256 kbps	Near-lossless	~1.9 MB	Audiophile, archival AAC

Note: AAC is more efficient than MP3, so 128 kbps AAC sounds comparable to 160–192 kbps MP3. Match or exceed the source WMA bitrate to minimize quality loss.

WMA vs. AAC — At a Glance

WMA (Windows Media Audio)

Slightly better compression than MP3 at same bitrate
Native support on Windows, Xbox, and older portable players
WMA Lossless variant available for archival quality
Proprietary Microsoft format with limited cross-platform support
Not supported natively on iOS, Android, or most streaming platforms

AAC (Advanced Audio Coding)

Supported natively on iOS, macOS, Android, and all major streaming platforms
Better audio quality than MP3 at equivalent bitrates
Default audio format for YouTube, Apple Music, and iTunes purchases
Lossy only — no lossless AAC variant (use ALAC or FLAC for lossless)
Some older non-Apple hardware players have limited AAC support

Copied!

Summary

Inspect your WMA file metadata in the browser and generate the perfect FFmpeg command to convert it to AAC at your chosen bitrate — no upload required.

How it works

Drop a WMA file onto the inspector panel (or click to browse).
The Web Audio API reads the file's sample rate, duration, and channel count locally.
Choose an AAC bitrate — 128 kbps for casual listening, 192 kbps for high quality, 256 kbps for near-lossless fidelity.
Copy the generated FFmpeg command and run it in your terminal.
Verify the output AAC file in a player before deleting your original WMA.

Use cases

Convert a WMA music library to AAC for playback on iPhone, iPad, or Apple TV.
Prepare WMA recordings for upload to YouTube, SoundCloud, or other streaming platforms.
Transfer WMA files from Windows Media Player to Android, iOS, or a modern car stereo.
Batch-convert an entire WMA album by adapting the single-file command into a shell loop.
Check a WMA file's sample rate and duration before encoding to AAC.
Estimate the output AAC file size before committing to a bitrate.
Generate a ready-to-paste FFmpeg command without memorizing its flags.
Compare WMA and AAC characteristics side-by-side before deciding on a format.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu