Social media is always on.

Determining the best times to post on Facebook, Twitter, Google+, Pinterest, LinkedIn, and blogs is vital to
content marketing
success. The optimal time to share on each platform may vary depending
on your audience, of course. The nature of your business and data about
when your audience is active should inform and drive your timetable so
that you maximize your reach and
virality.
Social media timing tools
There are many tools you can use to gauge your timing.
HootSuite’s
functionality enables you to automatically schedule your Twitter,
Facebook, and LinkedIn updates based on your followers’ engagement
patterns. A great app I just discovered called
SocialBro
analyzes the timelines of your followers and creates a “best time to
tweet” report that tells you when you should be tweeting to maximize
retweets and replies.
Topsy, an app that has been around for a few years, performs social network trend analysis.
Timing+ helps you decide when it’s best to post on Google+ by evaluating your historical post data.
SocialFlow
uses real-time data to understand the constantly changing interests of
your audience and maps your content to the windows where you’ll get the
most attention.
When to post on Facebook, Twitter, Google+, Pinterest, LinkedIn, and blogs — and when not to
Fannit combed the Web and aggregated the timing information below, which you can use as a general guideline for U.S. time zones.
Best times: Weekdays 6:00-8:00am and 2:00-5:00pm
Worst times: Weekends 10:00pm-4:00am
Best times: Weekends 1:00-3:00 pm
Worst times: 8:00pm-8:00am
Best times: 9:00-11:00am
Worst times: 6:00pm-7:00am
Best times: 7:00-8:30am, 5:00-6:00pm
Worst times: Monday and Friday, 9:00am-5:00pm
Best times: Saturday, 2:00-4:00am and 8:00-11:00pm
Worst times: 1:00-7:00am and 5:00-7:00pm
Best times: Monday, Friday, and Saturday at 11:00am
Worst times: 11:00pm-8:00am
When to Post on Facebook, Twitter, Google+, LinkedIn, and Pinterest is a post by Pam Dyer on Pamorama | Social Media Marketing Blog.
A Forbes Top-50 Forbes Social Media Power Influencer, Pam is a
Seattle-area marketing professional and Seahawks fan. Follow her on
Twitter at @pamdyer