The best way to determine the optimum post lengths for your business and your audience is to analyse your data, which posts received the most retweets/shares? Which posts achieved the highest levels of engagement?
Analysing the data that is specific to your business and audience will give you the most accurate answer to the question. However, we can create guidelines based on studies and research and come up with a good rule of thumb.
So what are the optimum lengths for your digital marketing efforts (social media marketing, email marketing, websites, content marketing, blog posts etc), take a look at my at a glance guideline table:
Remember there are no hard and fast rules and these are only intended to be used as guidelines, making your email subject line or Facebook post longer will not result in failure and making them the exact length will not guarantee success.
Your content should be as long as it needs to be to convey the desired message and no longer!