For me, the most important one is at which point does the content work better in a single column.
Before that, when do columns of text get so long and skinny and/or photos so small that it would be better to go from 3 or 4 columns to 2.
Both Firefox and Chrome have good ways to test your site at different breakpoints so you can see just where your content "breaks". You might find that a breakpoint down to one column makes more sense at 519px rather than a more 'standard' 480px. Do what works best to make your content easy to read/use.
Hi Paintbrush
I was looking for a way to test a finished site for breakpoints and saw your post.
Not familiar with Chrome perhaps you could help me and explain how I test my site in Chrome to see where my breaks and how it looks
Thanks
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