Bluetooth AAC is the codec Apple and Beats headphones use on wireless links: Apple names the Apple AAC Bluetooth Codec for its AirPods lines and most Beats models. Published rates differ by context: 264 kbps as a comparison-table maximum, 320 kbps as Android's A2DP default with variable bitrate. Measured lag on a four-phone Android rig averaged 369 ms, the worst in that program; RTINGS dropped AAC from its own bench over macOS measurement doubts. iPhones negotiate AAC and SBC only.
Figures on this page were checked September 2026. Every table row carries its source and access date.
Spec summary
AAC is the lossy digital audio compression standard that Apple's ecosystem leans on for Bluetooth: Apple states its AirPods lines and most Beats wireless headphones run the Apple AAC Bluetooth Codec.
| Field | Value | Source / as of |
|---|---|---|
| Type | Lossy digital audio compression standard, license-free | SoundGuys codec overview, 2026-09-22 |
| Role on Apple hardware | Apple AAC Bluetooth Codec, used by AirPods 3 or earlier, AirPods Pro 1, AirPods Pro 2 with Lightning Charging Case, AirPods Max and most Beats wireless headphones | Apple Support, "About lossless audio in Apple Music", 2026-09-22 |
| Cited maximum bitrate | 264 kbps, 16-bit, 44.1 kHz | SoundGuys comparison table, 2026-09-22 |
| Android stack configuration | 320 kbps default with variable bitrate support | AOSP a2dp_aac.cc (A2DP_AAC_DEFAULT_BITRATE), 2026-09-22 |
| Bluetooth transport | Windows 11 22H2 lists the Advanced Audio Distribution Profile (A2DP 1.3.2) among supported profiles | Microsoft Learn, General Bluetooth support in Windows, 2026-09-22 |
One naming note before the numbers: the codec inside Apple hardware and the one negotiated over an Android link are implementations of the same standard, measured and documented differently by each platform owner. This page keeps those contexts separate rather than averaging them.
Bitrate and real-world behavior
| Context | Rate | Source / as of |
|---|---|---|
| Comparison-table maximum | 264 kbps (16-bit, 44.1 kHz) | SoundGuys comparison table, 2026-09-22 |
| Android A2DP default | 320 kbps, variable bitrate | AOSP a2dp_aac.cc, 2026-09-22 |
| User-selectable ladder | None published; iOS exposes no codec or rate settings | General guidance, 2026-09-22 |
Two different numbers belong on this page because they describe different things. The 264 kbps figure is a maximum in a published comparison table; the 320 kbps figure is the configuration constant in Android's A2DP source, which also carries variable-bitrate flags. Neither is an Apple rate: the official Apple page names the codec but publishes no bitrate for it. A Bluetooth link negotiates the rate it uses, so treat any single number as configuration context rather than a guaranteed payload. The cross-codec rate view is our bitrate bench.
Measured latency
| Metric | Measured | Source / as of |
|---|---|---|
| Phone-to-headphone lag, Android | 369 ms average across four Android phones, the worst performer in the program; average variation 45 ms, up to 90 ms on two handsets | SoundGuys (Bluetooth receiver + instrumentation rig, not headphones), published 2021-03, accessed 2026-09-22 |
| iOS and macOS lag | No archived number: RTINGS excluded AAC from its latency solution after macOS measurements, around 45 ms on AirPods Pro (2nd gen), looked like audio compensation rather than codec lag | RTINGS latency research, accessed 2026-09-22 |
| Expectation baseline | "Expected to be, at the minimum, as low latency as SBC" | RTINGS latency research, attributed expectation, accessed 2026-09-22 |
The 369 ms figure comes from one measurement program on Android hardware, in the same program that called AAC its worst and most variable codec. iOS numbers are harder to archive honestly: RTINGS measured around 45 ms on a Mac setup, rejected its own result as a compensation artifact, and dropped AAC from the bench. For fixes that work regardless of codec, our Bluetooth audio delay guide covers the radio-side options. The cross-codec view is our latency bench.
Device and OS support
| Platform / device | AAC support | Source / as of |
|---|---|---|
| iPhone / iPad | Yes, alongside SBC; "iPhones only support the AAC and SBC Bluetooth codecs" | SoundGuys codec support article, 2026-09-22 |
| Apple and Beats headphones | AirPods 3 or earlier, AirPods Pro 1, AirPods Pro 2 with Lightning Charging Case, AirPods Max and most Beats wireless headphones use the Apple AAC Bluetooth Codec | Apple Support, 2026-09-22 |
| Android phones | Yes; the AAC encoder ships in the Android Open Source Project Bluetooth stack, configured at 320 kbps by default, with per-device results varying by handset | AOSP a2dp_aac.cc + SoundGuys codec overview, 2026-09-22 |
| Windows 11 | A2DP 1.3.2 listed among supported profiles; Windows AAC reported as xHE-AAC | Microsoft Learn + RTINGS latency research, 2026-09-22 |
| Third-party transmitters | Varies by model; check the codec list of the specific unit | General guidance, 2026-09-22 |
Pairing behavior
AAC links negotiate the way A2DP links do: both ends list their codecs and the source picks. An iPhone paired to an AAC-capable receiver stays inside its two-codec menu, which is why AAC is the default state of the Apple ecosystem. Android phones negotiate among SBC, AAC and higher-rate codecs such as LDAC depending on what both ends support, and Qualcomm's aptX HD plays by the same rule from the other side. Per-model detail lives in our iPhone codec compatibility page.
FAQ
No. Apple states plainly that Bluetooth connections aren't lossless, even on its own AirPods lines that use the Apple AAC Bluetooth Codec. Lossless Apple Music playback needs a wired path, such as the USB-C connection on newer AirPods Max.
iPhones negotiate AAC and SBC only, and Apple's own headphones run the Apple AAC Bluetooth Codec according to Apple. A Bluetooth link can only use what both ends advertise, so the codec set of the source decides the outcome.
In the SoundGuys program, AAC averaged 369 ms across four Android phones with the widest variation of the codecs tested, and the authors note AAC performance depends heavily on the source device. Their own caveat applies: the data was collected several years ago, so newer phones may do better.
There is no single published rate. Comparison tables cite a 264 kbps maximum, Android's A2DP stack configures 320 kbps with variable bitrate, and Apple publishes no bitrate for the Apple AAC Bluetooth Codec. The link negotiates the rate, so treat each number as configuration context.
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- Apple Support, "About lossless audio in Apple Music": "AirPods 3 or earlier, AirPods Pro 1, AirPods Pro 2 with Lightning Charging Case, AirPods Max, and most Beats wireless headphones use Apple AAC Bluetooth Codec to ensure excellent audio quality. However, Bluetooth connections aren't lossless." support.apple.com/en-us/118295, accessed 2026-09-22
- Microsoft Learn, General Bluetooth support in Windows: Windows 11 version 22H2 profile table lists Advanced Audio Distribution Profile A2DP 1.3.2. learn.microsoft.com/en-us/windows-hardware/drivers/bluetooth/general-bluetooth-support-in-windows, accessed 2026-09-22
- Android Open Source Project, a2dp_aac.cc: A2DP_AAC_DEFAULT_BITRATE 320000 (320 kbps), variable-bit-rate enabled and disabled configurations, 44.1 kHz sampling entries. android.googlesource.com/platform/packages/modules/Bluetooth/+/refs/heads/main/system/stack/a2dp/a2dp_aac.cc, accessed 2026-09-22
- SoundGuys, Bluetooth codec support for headphones: comparison table (AAC 264kbps / 16-bit / 44.1kHz) and "iPhones only support the AAC and SBC Bluetooth codecs." soundguys.com/bluetooth-codec-support-headphones-61989/, accessed 2026-09-22
- SoundGuys, "Android's Bluetooth latency needs a serious overhaul": AAC 369 ms average across four Android phones, worst performer, 45 ms average variation and 90 ms on two handsets; measured with a Bluetooth receiver and instrumentation, not headphones. soundguys.com/android-bluetooth-latency-22732/, accessed 2026-09-22
- SoundGuys, "Understanding Bluetooth codecs": AAC as the lossy digital audio compression standard, license-free for YouTube and Apple devices; Android results vary by source device, with the authors' caveat that their data is years old. soundguys.com/understanding-bluetooth-codecs-15352/, accessed 2026-09-22
- RTINGS, "Test Bench 1.6: Latency R&D Article": Apple AAC Latency section; macOS AAC results (~45 ms on AirPods Pro 2nd gen) treated as compensation artifacts, AAC excluded from the final solution; "While Windows 11 introduced support for AAC, it uses xHE-AAC." rtings.com/headphones/learn/research/latency, accessed 2026-09-22