What font size should I use when I am creating an academic poster?
There are two criteria for text on a poster:
Text on the poster must be readable from a distance of a metre or so
Restrict your word count to only a few hundred words. I recommend 600-800
Taking those together, I suggest the following font sizes are a good starting point:
Titles 72+ Sub-titles 54+ Text 30+ Sub-text 20+
Obviously the actual font used can effect this. I tend to keep to a standard sans-serif font such as Arial or Helvetica (or my favourite Trebuchet). The values are, as I say, a starting point and will need to be changed (usually increased) to suit the design of the poster.