How to judge noise-cancelling headphones before you buy

Noise cancelling is a system, not a number

Active noise cancelling works by sampling the noise around you and playing the opposite waveform. It is most effective on steady low-frequency sound: engine drone, air conditioning, the rumble of a train. Sudden or high-pitched sound is handled far less well, which is why voices in a cafe still come through even on the best pairs.

The number of microphones on the box tells you little on its own. Placement, processing and the seal around your ears decide what you hear.

Fit decides how much cancelling you actually get

A loose seal loses both bass and passive isolation, and no amount of processing recovers it. Earcup clamp and pad depth matter if you wear glasses, and headband pressure matters over a long flight. Try the pair on before you commit if you can.

Battery life depends on how you use it

Manufacturer figures usually assume a moderate volume with cancelling on. Transparency modes, higher volume, spatial audio and lossless codecs all draw more. A pair rated for a long-haul flight may still need a charge on a commute week.

Codecs, multipoint and calls

Multipoint pairing keeps a laptop and a phone connected at once, which is the feature most people miss once they have it. Codec support only matters if your source devices support the same ones.

How we compare them

Each pair in our comparison is set against the same rows: cancelling type, codec support, multipoint and rated battery. See the noise-cancelling headphones comparison.