AIFF to AC3 Converter

AIFF vs AC-3: Which Should You Convert To?

AIFF is uncompressed linear PCM; AC-3 is Dolby Digital, a lossy codec built for delivery. The short answer is that this conversion is worth doing when something downstream demands a Dolby bitstream — DVD or AVCHD authoring, an AV receiver fed over S/PDIF, or a video mux where a PCM track is simply too fat. If the file is going to a phone, a car, a website or an editing timeline, AC-3 is the wrong target and you want MP3, AAC, FLAC or the original AIFF instead. Either way the AIFF stays your master: encoding to AC-3 is one-way.

Side-by-side Comparison

When AC-3 Is the Right Target

• You are authoring a DVD or AVCHD disc. DVD-Video players are required to decode Dolby Digital and linear PCM, so authoring tools ask for an AC-3 track — and AC-3 fits several times more running time on the disc than PCM does.
• You are feeding an AV receiver. A receiver that accepts a Dolby bitstream over optical, coaxial or HDMI decodes AC-3 directly, including its channel layout, rather than relying on the source device's own mixer.
• You are replacing a PCM track inside a video file. Swapping a 1,411 kbps PCM track for a 448 kbps AC-3 track saves roughly a gigabyte per hour of video with no change to the picture.
• The target is a TV, set-top box or media player with a published codec list. AC-3 appears on nearly all of them; it is one of the most widely implemented audio codecs in consumer hardware.

When to Keep AIFF or Choose Something Else

• Archiving or further editing. Every AC-3 encode throws data away permanently. Keep the AIFF, or move to FLAC if you want the same samples in half the space.
• Phones, browsers and general playback. No mainstream mobile OS or web browser decodes a bare .ac3 file; MP3 or AAC will play everywhere AC-3 does and everywhere it does not.
• High-resolution masters. AC-3 stops at 48 kHz, so a 96 kHz or 192 kHz session is resampled on the way in.
• You are hoping to create surround. AC-3 can carry 5.1, but it cannot invent channels. A stereo AIFF encodes as 2.0 AC-3, and a five-channel result would just be silent padding.

How to Convert AIFF to AC3

1. Upload Your AIFF File: Drag .aif or .aiff files onto the page or click "+ Add Files". Several files can be queued and share one set of settings.
2. Choose a Bitrate: In File Compression, either leave Preset on a quality level or switch to Constant Bitrate and pick a figure — the dropdown runs from 32 kbps to 384 kbps. Custom Bitrate takes an exact number if you need 448 or 640 kbps.
3. Set Audio Channel and Sample Rate: Leave Audio Channel on ORIGINAL to keep the source layout, or fold to STEREO or MONO. Set Audio Sample Rate to 48000 HZ for disc and broadcast work; Trim exports a start time and duration if you only need a section.
4. Convert and Download: Click Convert and save the .ac3. No sign-up, no watermark.

Bitrate and Channel Guide

Frequently Asked Questions

Will converting AIFF to AC-3 reduce the audio quality?

Yes, and permanently. AIFF holds every sample as recorded; AC-3 is a perceptual codec that discards what its model says you will not hear, and converting the result back to AIFF later restores the container, not the detail. At 384-448 kbps for 5.1 or 192-224 kbps for stereo, the difference is hard to hear on typical home-theatre gear — but always keep the AIFF as the master and treat the AC-3 as a delivery copy.

Will a stereo AIFF become real 5.1 surround?

No. AC-3 supports up to 5.1 discrete channels, but encoding cannot fabricate information that was never recorded. A two-channel AIFF becomes a 2.0 AC-3 stream. Genuine 5.1 output needs a source that already carries six discrete channels — L, R, C, LFE, Ls and Rs — and the Audio Channel control on this page offers ORIGINAL, MONO and STEREO, so it will fold channels down but never up.

What bitrate should I use for a 5.1 track on a DVD?

448 kbps is the DVD-Video maximum and what commercial discs typically use for 5.1; the Constant Bitrate dropdown here stops at 384 kbps, so type 448 into Custom Bitrate if you want the ceiling. 384 kbps is the practical floor for surround before rear channels and the LFE start to thin out. For Blu-ray you can go to 640 kbps, which is the highest rate the AC-3 standard defines.

Does the AC-3 keep my file's sample rate and bit depth?

Sample rate only up to a point, and bit depth not at all. AC-3 defines exactly three sample rates — 32, 44.1 and 48 kHz — so a 96 kHz master is resampled, and the lower entries in the Audio Sample Rate dropdown (8, 12, 16 and 24 kHz) are not valid AC-3 rates; leave the control on ORIGINAL or choose 48000 HZ. Bit depth is not a meaningful concept once audio is perceptually coded: the encoder stores frequency-domain coefficients, not 16- or 24-bit samples.

How much smaller will the AC-3 be than the AIFF?

Both are constant-rate formats, so the answer is arithmetic. Our encoder writes a fixed bitrate: three minutes of 44.1 kHz 16-bit stereo AIFF is 44,100 × 2 × 2 × 180 ≈ 31.8 MB, while the same three minutes at 192 kbps is 192,000 ÷ 8 × 180 ≈ 4.3 MB, and at 448 kbps ≈ 10.1 MB. Multichannel sources cost nothing extra in AC-3 — the bitrate you choose is the whole file size, however many channels it carries.

Can I play an .ac3 file on my phone or in a web page?

Generally not without help. AC-3 is a raw elementary stream aimed at hardware decoders, so mobile OSes and browsers usually refuse it, while desktop players such as VLC and mpv handle it fine. If the file needs to play on a phone, convert to MP3 instead and keep AC-3 only for the receiver or the disc.

Will song titles or artist tags survive the conversion?

No. A .ac3 file is a bare sequence of AC-3 sync frames with no tag container at all, so nothing from the AIFF's NAME, AUTH or ANNO chunks has anywhere to go. Once you mux the stream into MKV, MP4 or a DVD/Blu-ray structure you can label the track there.

Can I mux this AC-3 back into a video file?

Yes — that is the usual reason to make one. The .ac3 output is a standard elementary stream, so authoring tools and muxers accept it directly and align it to the video's timeline. Keep the encode at 48 kHz when you do this, because video containers and disc specs assume that rate.

Are my files private when I convert them here?

Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared or made public.

Going the other direction, or need the Dolby track unpacked for editing? See AC3 to AIFF.