Video to AAC Converter

How to Convert Video to AAC Online

1. Upload Your Video File: Drag and drop or click "+ Add Files" to select MP4, MOV, MKV, AVI, WebM, FLV, MTS, AVCHD, WMV, or 30+ other video formats. Batch conversion is supported — process multiple files with the same settings.
2. Pick a Bitrate under File Compression: File Compression opens on Quality Preset, the hands-off mode and the least predictable control on this page — see the FAQ below. Use Constant Bitrate to lock to a value like 128, 192, or 256 kbps (the ladder runs 8-384 kbps and sits on 128), Variable Bitrate for one of the five size-efficient AAC bands (96k-112k down to 20k-32k), Custom Bitrate for a precise number, or Specific file size to cap the output in MB.
3. Trim, Sample Rate, Channels (Optional): Use Trim to extract just a section (set start time and duration), Audio Sample Rate to downsample (e.g., 44.1 kHz to 22.05 kHz for voice), or Audio Channel to switch from stereo to mono and roughly halve the file size.
4. Convert and Download: Click "Convert". Files process on our servers and the AAC drops into your downloads — no sign-up, no watermark, no software install.

Why Convert Video to AAC?

AAC (Advanced Audio Coding) is the audio codec that powers YouTube, Apple Music, Spotify, and the iTunes Store. Standardized in ISO/IEC 13818-7 (MPEG-2 Part 7, 1997) and extended in ISO/IEC 14496-3 (MPEG-4 Part 3, 1999), it delivers audibly transparent stereo at ~128 kbps VBR — a bitrate where MP3 still shows artifacts. Extracting just the AAC track from a video is much smaller than keeping the whole file and lets the audio play natively on phones, car stereos, and smart speakers.

• Audiobook / podcast workflow — Strip the AAC from a long lecture recording or video interview and load it onto an iPhone or Apple Watch. Apple's ecosystem treats AAC as a first-class citizen, so chapter markers, metadata, and AirPlay handoff "just work."
• Save space on long recordings — A 1-hour 1080p MP4 at 8 Mbps is roughly 3.6 GB; the AAC audio track at 128 kbps is around 56 MB. If you only need the audio (lectures, sermons, interviews), the storage savings are 60-100x.
• Sample audio for editing — DAWs like Logic Pro, GarageBand, and Pro Tools open AAC natively. Extract speech, ambient sound, or music from a video shoot so you can re-edit it without re-rendering the full clip.
• Ringtones and notification sounds — Android and many car infotainment systems accept .aac directly; iOS uses .m4a (same AAC codec inside an MP4 container). Trim a 10-30 second clip and you have a custom ringtone.
• Embedding into web pages and apps — The HTML5 <audio> element supports AAC across Chrome, Firefox, Safari, and Edge, and AAC is the recommended codec for HLS streaming. Smaller files load faster and use less mobile data.
• Move into MP4 / M4A — Once you have a clean AAC track, you can wrap it in an MP4 container or rename to .m4a for Apple-friendly tagging. See Convert Video to M4A if you want the M4A container directly.

AAC vs MP3 vs M4A — Format Comparison

AAC Bitrate Quick Guide

Frequently Asked Questions

Will my video's audio quality drop when I extract it as AAC?

If the source already uses AAC (most MP4s do), pick a bitrate at or above the source's bitrate to avoid a second lossy pass. Our default of 128 kbps is transparent for typical stereo material, but if you know the source is 256 kbps AAC, choose 256 kbps — the audio is always re-encoded, so matching the source bitrate keeps that re-encode near-transparent instead of stepping down to a lower quality.

What's the difference between .aac and .m4a if both use the AAC codec?

The codec inside the file is identical — AAC frames. The difference is the wrapper. A .aac file is a raw ADTS stream (just AAC frames with sync headers); a .m4a file is an MP4 container that holds the same AAC plus metadata atoms for title, artist, album art, and chapter markers. Apple devices prefer .m4a; older Android car stereos sometimes prefer .aac. If you want M4A specifically, use Convert Video to M4A.

Can I trim the video first so I only get the audio I need?

Yes. Open the Trim group, set a start time and a duration. For example, start 00:01:30 and duration 60 to extract a 1-minute clip starting 90 seconds into the video. This runs as part of the conversion — you don't need a separate trim step.

Why is my AAC file larger than I expected?

Three usual culprits: (1) you picked a high bitrate like 256 or 320 kbps without realizing, (2) the source is multi-channel (5.1 surround) and AAC is preserving all channels — switch Audio Channel to stereo or mono to shrink it, or (3) the duration is longer than you remember. As a sanity check: 128 kbps stereo = ~1 MB per minute.

Should I pick Variable Bitrate or Constant Bitrate?

Variable Bitrate is the more efficient of the two — bits are spent on complex passages and saved on silence, across five AAC bands running from 20k-32k up to 96k-112k. Constant Bitrate is more predictable for streaming and easier to reason about ("256 kbps for 60 minutes = 115 MB"). For local playback, pick a Variable Bitrate band; for HLS streaming or strict size budgets, pick Constant Bitrate. Quality Preset sits outside this comparison: it is the hands-off mode, with nothing pre-selected in its dropdown, and the least predictable control on the page — reach for it only when the exact output rate is not something you need to pin down.

Does AAC work on Android, Windows, and Linux, or is it Apple-only?

AAC plays everywhere modern. Android has supported AAC playback since 1.0 (2008), Windows since Windows 7, and major Linux distributions ship FFmpeg-based players that decode AAC. The "Apple-only" reputation comes from .m4a files (which sometimes confuse non-Apple software) — the codec itself is universal. Chrome, Firefox, Safari, and Edge all support AAC in HTML5 audio.

Can I convert AVCHD / MTS / MKV / WMV files, not just MP4?

Yes. The tool accepts 30+ video formats including MP4, MOV, MKV, AVI, WebM, FLV, MTS, M2TS, AVCHD, WMV, VOB, 3GP, MPEG, OGV, and more. The audio track gets re-encoded to AAC regardless of the input container.

How does this compare to extracting MP3 instead?

If your target device or workflow is Apple-centric, AAC is better — same perceived quality at roughly 15–20% smaller size. If you need maximum compatibility with old car stereos, USB sticks, and 2000s-era devices, MP3 wins on universal support. For modern phones, web players, and streaming, AAC is the right choice. See Convert Video to MP3 for the MP3 path.

Is there a way to keep the original AAC track without re-encoding?

Our tool always runs the audio through an encoder pass, which is the right behavior when you're changing bitrate, channels, or sample rate. If you want a bit-perfect copy of the original AAC track and the source already uses AAC, FFmpeg's -c:a copy flag is the way to do that locally. For everything else (different bitrate, trim, channel change), re-encoding is required.