How To Pronounce Fast

In British English, fast is pronounced /fɑːst/. The narrow phonetic transcription is [fɑːst̚]. In American English, it is pronounced /fæst/.

Fast has one syllable. The British and American pronunciations are different, so listen to both.

Slashes / / show the phonemic transcription, the sounds that change meaning. Square brackets [ ] show the phonetic transcription, with the finer detail of how the sounds are actually made.