say -v Alex "Hello"

Is there a way to change the speed of speech like there is in the speech settings of System Preferences -> Date & Time -> Clock -> Customize Voice?

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3 Answers 3


Yes, there is. The command

say -v Alex "Hello" -r 200

will cause the voice Alex say "Hello" at a rate of 200 words/minute.

  • 2
    Also, I'd like to point out (with no rudeness intended) that this is easily found in the manpage for say. man [programname] will bring up the documentation for most unix command line applications. Nov 22, 2013 at 1:21
  • -r --rate= wasn't working for me on 10.13 for /usr/bin/say, but the embedded speech command below did. Was using -v Tom.
    – Pysis
    May 13, 2018 at 14:22
  • 1
    What is the default rate? May 28, 2020 at 10:44
  • 3
    @FelixJassler The default rate is 200 Feb 11, 2021 at 23:48

There is also an embedded speech command for changing the rate:

say '[[rate 200]] hello'
  • 1
    Unfortunately, most of the new voices added by Apple since 10.6 will ignore embedded commands for speech rates and phoneme preferences. :( Really annoying, since I love the Fiona voice pack, but she occasionally mis-pronounces some words so horribly that they're unrecognisable. :( Mar 31, 2014 at 22:30
  • Interestingly, this works in HTML documents with Apple Speech Synthesis hotkey and the JS Speech Synthesis API.
    – joeyhoer
    Nov 20, 2017 at 21:34
  • Seems to work as of 10.12, even with the very realistic voices like Thomas. Super creepy at 40 wpm :D
    – iwasrobbed
    Apr 26, 2018 at 2:24
  • doesn't seem work (nor does --rate with localized voices such as Luca and Alice) on 10.14
    – riffraff
    Jul 26, 2019 at 8:14
  • 2
    It's okay with me to use say "[[rate +500]] hello" ;) As the document says.
    – wind2412
    Sep 15, 2019 at 2:54

FWIW: I'm on Big Sur and the -r/--rate is simply ignored. However, the embedded command as described by @lri still works.

P.S. I see in an earlier comment that 10.13 also had that issue. Well...

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