My Dell laptop (XPS 15z) has special keys on the F1 to F12 keys. If I want to disable keyboard backlight, for example, I must type Fn + F6.

  • Is it possible to invert it?

In fact, I don't often use the F* keys.

  • How can I only hit F6 to disable the backlight and Fn + F6 to type F6?

  • Is it possible?


  • People here I recommend going to the top voted answer not the accepted answer. It is much easier to do ctrl-esc than to mess around in bios. FYI.
    – neuronet
    Jun 22 '17 at 0:49
  • 1
    I updated the accepted answer.
    – Gp2mv3
    Jan 5 '18 at 11:13
  • You can switch behaviour of function keys (to function with or without Fn key).. use Fn + Esc (fn padlock icon icon) Jul 15 '19 at 3:55

I am not sure if it works for all models, but on mine if you press Fn+Esc it changes the Fn lock so that F1+F12 work as normal and when you hold Fn+(lets say F11) it will change the brightness or whatever that keys secondary function is. Pressing Fn+Esc again reverts it back to default. Hope this helps.

  • 17
    Gah, thank you for posting this! I accidentally pressed this without even realizing such a feature exists. Would go hunting around BIOS if you hadn't helped!
    – kaqqao
    Nov 11 '15 at 0:31
  • 1
    Wow that is an awful default toggle to have on a row that is so similar to the intended row. Why this isn't the accepted answer is a rare glitch in the SO matrix.
    – neuronet
    Jun 22 '17 at 0:48
  • 2
    This is a better answer as it is an easier option. Wondering why this is not marked as answer!
    – Raul
    Jul 29 '17 at 1:41
  • 3
    I always did it changing BIOS but didn't found this option in my new notebook. Fn+Esc worked, to be honest Esc even has a padlock icon but I was unable to figure out alone.
    – iurisilvio
    Jun 8 '18 at 15:46
  • 1
    Pressing Function Key + Shift make it inverted in HP EliteBook Laptop Jun 27 '19 at 15:13

It should be possible to do it in the BIOS. Quoting the XPS 15z manual:

  1. Press F2 during POST (Power On Self Test) to enter the System Setup (BIOS) utility.

  2. In the Function Key Behavior, select Multimedia Key First or Function Key First.

    • Function Key First — This is the default option. Press any function key to perform the associated function. For multimedia action, press Fn + the required multimedia key.
    • Multimedia Key First — Press any multimedia key to perform the associated multimedia action. For function, press Fn + the required function key.
  • This works for a different model Dell laptop I have as well, and I would suspect for anything else with Dell's BIOS (don't have experience with any other vendors).
    – zpletan
    Mar 13 '12 at 14:11
  • This also works for my Lenovo (Flex 2) Laptop. No 2 options as mentioned above, just an enable and disable option.
    – blo0p3r
    Sep 18 '14 at 3:36
  • 6
    On a new Dell XPS 13, the option is under "POST Behavior", "Fn Lock Options"
    – JavadocMD
    Jun 18 '15 at 20:59
  • 1
    If enabled in the BIOS (which I assume it is by default), you can toggle the behavior of the Fn key with the Fn+Esc hotkey.
    – airstrike
    Jan 31 '16 at 22:11

On mine, the problem was that the NumLk key had been pressed. Pressing it again holding the Fn key reverted the Fn key back.

  • This works for my laptop only 1 time (1 F-key click) after pressing and loding NumLk+Fn. Then it does not work again. Dec 7 '18 at 13:54

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