X AAC Encoder 1.0

For over a decade, anyone who wanted to encode audio to AAC on Windows using the open-source FAAC engine had two options: run faac.exe from the command line, or fall back on the original FAAC GUI - a minimal front-end with about five settings, no batch queue, no metadata panel, and no cover art support.

X AAC Encoder 1.0 closes that gap.

It exposes every FAAC option through a clean modern interface, adds batch encoding across a folder tree, embeds full MP4 tags including artwork, and transparently decodes MP3, FLAC, OGG, OPUS, WMA, APE, and audio from video containers through a bundled FFmpeg build.

Why a New FAAC GUI Matters in 2026

AAC remains the default audio format for iTunes, YouTube, MP4 video, and most streaming services, which keeps FAAC relevant for Windows users who want a fully free and redistributable encoder without installing iTunes (the requirement for Apple AAC via qaac) or relying on Nero's discontinued toolchain (see Nero AAC Codec).

The FAAD2 and FAAC bundle ships the raw encoder and decoder, but both are command-line tools. For users who want a graphical workflow, FAAC has been effectively a power-user format for years.

X AAC Encoder changes that. It is built around the same battle-tested FAAC 1.40 core that ships in the FAAD2/FAAC bundle on codecs.com, but it surfaces every encoder flag - joint stereo mode, Temporal Noise Shaping, Perceptual Noise Substitution, quantizer quality, bandwidth cutoff, block type control - with tooltips that explain what each option actually does.

The command that will run is always visible in a live preview pane, which doubles as a learning tool for anyone who will eventually want to script faac.exe directly.

What You Can Do With It

Batch encode entire folders

Drop a single file, a selection, or an entire folder into the queue. Each file shows its own progress bar and error state.

The batch can be cancelled at any point without leaving half-encoded files behind, and filename collisions are handled by a policy you choose - skip, overwrite, or auto-rename with (2), (3), and so on.

Encode from more than twenty input formats

WAV is read natively by FAAC. Everything else goes through a bundled FFmpeg build that decodes on the fly with no intermediate files.

That means you can feed in MP3, FLAC, OGG Vorbis, OPUS, M4A, AAC, WMA, APE, WavPack, AIFF, MKA, and audio tracks pulled from MP4, MKV, AVI, MOV, WebM, TS, and MPEG video files. If you need the standalone encoder for custom pipelines, the same FFmpeg builds are available on the FFmpeg download page.

Full MP4 tagging including cover art

Title, artist, album, album artist, composer, year, genre, track number, disc number, comment, compilation flag, and cover art are all editable per file or across the whole batch.

Point the cover art field at a JPEG or PNG and X AAC Encoder embeds it as MP4 artwork in the .m4a output. If you enable "Copy tags from source", metadata and artwork flow automatically from each input file, which makes re-encoding a tagged FLAC library to space-efficient AAC a one-click operation.

VBR, ABR, and six tuned presets

Six built-in presets cover most real use cases: Voice 64k, Podcast 96k, Music 128k, HQ Music 192k, Transparent, and Archival VBR. VBR mode uses a quantizer quality from 10 to 500 (100 is transparent for most music), and ABR locks the output to a target bitrate from 64 to 320 kbps.

You can save your own preset as a JSON file and load it on another machine, which is useful for anyone maintaining a consistent encoding profile across a studio or podcast team.

Live FAAC command preview

Before the encode starts, X AAC Encoder shows the exact faac.exe command it will run, with all flags resolved.

This is helpful in three situations: learning what each option does, debugging a misbehaving preset, and copying the command for a shell script when you want to automate the same encode later without the GUI.

AAC Format and Encoding Mode Guidance

AAC comes in several profiles and the right choice depends on bitrate and target playback device. The quick version: for normal music at 128 kbps and above, AAC-LC is what you want, and FAAC produces transparent results.

Below 96 kbps, HE-AAC (which uses Spectral Band Replication) sounds considerably better, but FAAC itself only produces AAC-LC - for HE-AAC output, the FDK AAC Codec from Fraunhofer is the correct tool, and the free-codecs.com guide on AAC vs AAC-LC vs AAC-HE walks through the tradeoffs in detail.

For output container, X AAC Encoder can write either .m4a (MP4 container with full metadata and cover art support - the right default for iTunes, phones, and virtually every modern player) or raw .aac streams (for streaming endpoints and hardware decoders with strict parsing rules). Raw AAC does not support tags, so cover art and metadata are only written to MP4 output.

Where X AAC Encoder Fits in the Audio Toolkit

X AAC Encoder is a specialist tool focused on AAC and M4A output. It is the right choice when you need modern AAC encoding with a GUI and do not want to install iTunes. For broader audio conversion workflows, it pairs well with a handful of other free tools on free-codecs.com:

For MP3 output instead of AAC, the LAME MP3 Encoder is the reference encoder, and LameXP wraps LAME, FLAC, Opus, and Ogg Vorbis encoders into a single drag-and-drop batch converter.

For a lightweight browser-based or portable alternative, X Audio Converter handles MP3 output without server uploads. For users who prefer a wizard-style interface, winLAME covers MP3, Ogg Vorbis, Opus, and FLAC through a step-by-step dialog.

If your target device supports it, Opus Audio Codec produces noticeably better quality than AAC at bitrates below 96 kbps and is the correct choice for voice, podcasts, and bandwidth-limited streaming. AAC is still the right pick when you need maximum compatibility with iPhones, car head units, and legacy hardware.

For decoding AAC content rather than encoding it, the FAAD2 side of the FAAD2 and FAAC bundle is the open-source reference decoder, and the AAC ACM Codec wraps FAAD2 as a Windows Audio Compression Manager component for legacy applications like VirtualDub.

How X AAC Encoder Compares to the Old FAAC GUI

The original FAAC GUI exposed roughly five controls: input file, output file, quantizer quality, MPEG version, and AAC object type. There was no batch queue, no metadata editor, no cover art field, no decoder support, and no preset system.

Files had to be converted one at a time, tags had to be added afterwards with a separate tool, and input was limited to WAV.

X AAC Encoder keeps everything that worked about the original - the same FAAC engine, the same command-line compatibility, the same free and open output - and adds the features every audio conversion workflow has needed for the past fifteen years. Joint Stereo, Mid/Side, and Intensity Stereo modes are accessible. TNS and PNS are toggleable with documented strength levels.

Frequency cutoff can be set manually or left to FAAC's auto mode. Filename templates accept {artist}, {album}, {title}, and {stem} placeholders. And the queue will happily chew through a folder of several hundred FLAC files in one run.

System Requirements and Installation

X AAC Encoder 1.0 runs on Windows 7, 8, 8.1, 10, and 11, on both 32-bit and 64-bit systems.

The installer is 10.3 MB and bundles everything the application needs - no .NET runtime, no Visual C++ redistributables, no Python.

A portable build is also available for USB sticks and locked-down corporate systems where installers are blocked. The program is genuinely free for personal and commercial use, contains no ads or bundled software, and runs entirely offline with no telemetry and no account requirement.

X AAC Encoder is the FAAC GUI that Windows users have been asking for since roughly 2010.

It takes the same open-source encoder that has been available on codecs.com for years, wraps it in a modern batch interface, and adds the metadata, cover art, and multi-format decoding that the original faacgui.exe never had.

For anyone who wants free AAC encoding on Windows without installing iTunes or touching a command line, it is the most capable option currently available.