Making subtitles (.srt) bigger or smaller with mpv

You can also add shortcuts to ~/.config/mpv/input.conf to adjust the subtitles size as you want.

# increase subtitle font size
ALT+k add sub-scale +0.1

# decrease subtitle font size
ALT+j add sub-scale -0.1

Note: if the config file doesn't exist, just create it in that location

The Manual has an entire section about subtitles.

2 relevant options:

  • --sub-scale=<0-100> just scale them
  • --sub-ass-force-style=<[Style.]Param=Value[,...]> Force specific style.

Add these to ~/.mpv/config by removing the leading double-dashees (--).

All of that only works for non-image based subtitle formats

Edit: @cipricus points out, that you can set shortcuts for increasing/decreasing subtitle size and position in the file ~/.config/mpv/input.conf

Inspired by the other answer - namely this:, where what it says is:

--sub-scale=<0-100> Factor for the text subtitle font size (default: 1).


This affects ASS subtitles as well, and may lead to incorrect subtitle rendering. Use with care, or use --sub-font-size instead.

Therefore, looking up --sub-font-size, we see this:

--sub-font-size= Specify the sub font size. The unit is the size in scaled pixels at a window height of 720. The actual pixel size is scaled with the window height: if the window height is larger or smaller than 720, the actual size of the text increases or decreases as well. Default: 55.

So - create the file config in a folder ~/.mpv with a line like


to get 80% of the 55 default size.

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