Batch encoding
Add files one at a time or drop an entire folder. Encode a hundred tracks with one click, with per-file progress and error reporting.
v1.2 - FAAC 2.2 + HE-AAC
The free AAC encoder for Windows
X AAC Encoder turns any audio or video file into AAC-LC or HE-AAC with batch processing, full tagging, and cover art. Powered by FAAC 2.2, wrapped in a clean modern interface. No ads, no spyware, no bundled software.
Already have FAAC 2.2 and FFmpeg? Download the app only (23 MB, .exe)
57.6 MB
Portable ZIP
20+
Input formats
100%
Free forever
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New in v1.2
- FAAC 2.2 inside - the retuned FAAC encoder, faster and sharper on transients.
- HE-AAC v1 - much better sound at 16-64 kbps for voice, podcasts, and streams.
- CBR and peak cap - constant bitrate for streaming, plus a per-frame bitrate ceiling.
- Retuned presets - new HE-AAC voice and podcast presets, VBR recalibrated for FAAC 2.2.
- Remembers your settings - and detects your FAAC version automatically.
// Features
Everything the old FAAC GUI never had
Built on FAAC 2.2, redesigned for how people actually convert audio in 2026.
Universal input
WAV natively, plus MP3, FLAC, OGG, OPUS, M4A, WMA, APE, and WavPack through the included FFmpeg. Even rips audio from video files.
Full metadata tagging
Title, artist, album, album artist, composer, year, genre, track, disc, comment, compilation flag, plus cover art embedded as MP4 artwork.
VBR, ABR, and CBR
Hold a quality level with VBR, an average bitrate with ABR, or an exact rate in every frame with CBR (16 to 320 kbps). Add a peak bitrate cap for strict transports.
AAC-LC and HE-AAC
Nine tuned presets, from Voice 32k HE-AAC to Archival VBR. Pick AAC-LC for music, HE-AAC for voice and streams, or let Auto decide.
Live command preview
See the exact FAAC command that will run before you start. Great for learning the FAAC flags or debugging your encoding pipeline.
MP4 or ADTS AAC
Output .m4a for maximum compatibility with iTunes, phones, and every modern player, or ADTS .aac for streaming and hardware with strict parsers.
Filename templates
Pick an output folder or write beside each source. Name files with {artist}, {album}, {title}, or {stem} placeholders pulled from source tags.
Zero telemetry
No calls home, no accounts, no registration. Runs fully offline. Fully portable - run it from a USB stick, no installation or admin rights.
// Input formats
Encode anything to AAC or M4A
WAV is read natively by FAAC. Everything else is transparently decoded through the included FFmpeg build before it reaches the encoder - no intermediate files, no manual conversion.
.wav
.mp3
.flac
.ogg
.opus
.m4a
.aac
.wma
.ape
.wv
.aiff
.mka
.mp4
.mkv
.avi
.mov
.webm
.ts
.mpg
.oga
.m4b
.mpeg
// Included components
Powered by FAAC and FFmpeg
Two proven open-source tools do the heavy lifting. Both are included in the portable download and sit next to the app, so you can swap in a newer build at any time.
// How it works
Four steps to AAC
From messy library to tagged AAC files in less time than it takes to make coffee.
01 / Add
Load files or folders
Drag in a mix of WAV, FLAC, MP3, OGG, and video files, or point at a whole folder for recursive scan.
02 / Configure
Pick a preset
HE-AAC voice and podcast, Music, Streaming CBR, Transparent, or Archival. Or skip presets and set the mode, profile, and stereo coding manually.
03 / Tag
Bring your metadata
Copy tags from source automatically, override for the whole batch, and drop in a cover art image.
04 / Encode
Hit Start
Watch the queue fly through. Cancel at any time, skip or auto-rename conflicts, and get a clean summary when done.
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// Under the hood
Every FAAC option, cleanly exposed
The old FAAC GUI showed four checkboxes. X AAC Encoder surfaces the full FAAC 2.2 feature set with tooltips that explain what each option actually does.
// Questions
Frequently asked questions
Common questions about AAC encoding, FAAC, and X AAC Encoder specifically.
What is X AAC Encoder?
X AAC Encoder is a free Windows desktop application that encodes audio files to AAC and M4A format. It is powered by FAAC 2.2 and encodes both AAC-LC and HE-AAC. It adds a modern batch-capable interface, metadata tagging, cover art embedding, and decoding of more than twenty input formats through an included FFmpeg build.
Is X AAC Encoder really free?
Yes. X AAC Encoder is completely free for personal and commercial use. The application itself contains no ads, no bundled software, no trial limits, no watermarks, and no calls home. Our website is supported by AdSense banner ads above and below the content, but nothing inside the program.
What input formats does it support?
WAV is read natively. Everything else is decoded on the fly through an included FFmpeg build: MP3, FLAC, OGG Vorbis, OPUS, M4A, AAC, WMA, APE, WavPack, AIFF, MKA, plus audio tracks from MP4, MKV, AVI, MOV, WebM, TS, and MPEG video files. If FFmpeg can read it, X AAC Encoder can encode it to AAC.
What is the difference between FAAC and Apple AAC?
Apple AAC is a proprietary encoder that ships with iTunes and macOS. FAAC is an open source AAC encoder that runs anywhere and is free to redistribute.
FAAC 2.x was heavily retuned in 2026, and the FAAC project's own objective benchmarks now place it level with or ahead of fdkaac and Apple AAC. Blind listening tests have not confirmed that yet. At 128 kbps and above, the difference is inaudible for most music.
FAAC 2.x was heavily retuned in 2026, and the FAAC project's own objective benchmarks now place it level with or ahead of fdkaac and Apple AAC. Blind listening tests have not confirmed that yet. At 128 kbps and above, the difference is inaudible for most music.
Do I need to install X AAC Encoder?
No. X AAC Encoder is portable. Download the ZIP, unzip it anywhere - including a USB stick - and run X-AAC-Encoder.exe.
FAAC 2.2 and FFmpeg are included, so it works straight away with no admin rights and no registry changes. Settings are saved in %APPDATA%\xcodecpack\aac-encoder.
FAAC 2.2 and FFmpeg are included, so it works straight away with no admin rights and no registry changes. Settings are saved in %APPDATA%\xcodecpack\aac-encoder.
What is HE-AAC and when should I use it?
HE-AAC (High Efficiency AAC) adds Spectral Band Replication, which rebuilds the high frequencies from a few bits of side data. It sounds far better than plain AAC-LC at 16 to 64 kbps, so it is ideal for voice, podcasts, audiobooks, and internet radio.
Above about 80 kbps, AAC-LC is the better choice. HE-AAC needs a source sample rate of 32 kHz or higher, and it plays on all modern phones, browsers, and players.
Above about 80 kbps, AAC-LC is the better choice. HE-AAC needs a source sample rate of 32 kHz or higher, and it plays on all modern phones, browsers, and players.
What is new in X AAC Encoder 1.2?
Version 1.2 moves to FAAC 2.2 and adds HE-AAC v1 encoding, a CBR mode, a peak bitrate cap, and Mixed joint stereo. It also brings new HE-AAC voice and podcast presets, VBR presets retuned for FAAC 2.2, automatic FAAC version detection, and settings that are remembered between sessions.
Does it support batch encoding?
Yes. Add any number of files or point at a folder for recursive scan, and X AAC Encoder will process the entire queue with the same settings. Each file can retain its own source metadata (title, artist, album, cover art) automatically, or you can override tags for the whole batch from the Tags panel.
Which is better, VBR or ABR?
VBR (variable bitrate) holds a quality level and gives the best quality per byte. ABR (average bitrate) gives predictable file sizes. CBR (constant bitrate) keeps every frame at exactly the target rate, which streaming servers and some hardware require.
With FAAC 2.2, VBR quality 250 averages about 130 kbps and 500 about 180 kbps on music. Note that FAAC 2.x uses a leaner scale than 1.x, where 100 meant roughly 128 kbps.
With FAAC 2.2, VBR quality 250 averages about 130 kbps and 500 about 180 kbps on music. Note that FAAC 2.x uses a leaner scale than 1.x, where 100 meant roughly 128 kbps.
Does it run on Windows 11?
Yes. X AAC Encoder runs on 64-bit Windows 10 and Windows 11. It needs no Python, .NET, or Visual C++ redistributable - the bundled FAAC 2.2 build uses the Universal C Runtime that is built into Windows.
Can I embed cover art?
Yes. Point the Cover art field in the Tags tab to a JPEG or PNG image and X AAC Encoder embeds it as MP4 cover art in the .m4a output. If you have Copy tags from source enabled, cover art is also pulled from each source file automatically. Raw .aac streams do not support metadata, so cover art only applies to the MP4 container output.
Is there a command-line version?
X AAC Encoder is GUI only. For command-line automation, use the included faac.exe and ffmpeg.exe directly from the X-AAC-Encoder folder. The Command preview pane in the Encoder tab shows the exact FAAC 2.2 command the app runs, ready to copy and script.
Can I update FAAC or FFmpeg separately?
Yes. faac.exe, libfaac-2.dll, and ffmpeg.exe sit next to the app in the X-AAC-Encoder folder. FAAC 2.x is two files, so always replace faac.exe and libfaac-2.dll together.
The app detects the FAAC version on launch and adapts its options, so an older FAAC 1.x build still works - just without HE-AAC, CBR, and the peak cap.
The app detects the FAAC version on launch and adapts its options, so an older FAAC 1.x build still works - just without HE-AAC, CBR, and the peak cap.
How does X AAC Encoder compare to the old FAAC GUI?
The original FAAC GUI (faacgui.exe) was a minimal front-end that exposed about five options: input file, output file, quantizer quality, MPEG version, and AAC object type. X AAC Encoder exposes every FAAC 2.2 option including HE-AAC, CBR, peak bitrate cap, joint stereo modes, PNS, TNS, block type control, bandwidth cutoff, and the full MP4 tagging flag set - plus it adds batch encoding, a file queue, decode support for twenty-plus formats, filename templates, save/load presets, and a modern dark interface.
Ready to encode?
Free forever. Portable - unzip and run, FAAC 2.2 and FFmpeg included.
Download X AAC Encoder 1.2Already have FAAC 2.2 and FFmpeg? Download the app only (23 MB, .exe)
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