For any link you share, the number of clicks displayed in Bitly could be different from the number of clicks you see in your social media or email accounts, like Facebook, Instagram, Mailchimp, Marketo, etc. This is because each platform measures clicks differently.
How Bitly counts clicks
When your shortened link is clicked, the click goes through Bitly to get to the destination page. What you're seeing with Bitly is the number of times a link is expanded from the short link to the long URL.
How other platforms count clicks
Other things that affect click counts
Bots, applications like browser plug-ins, and spam checkers in email programs might expand a shortened link without taking a user to the destination page. For instance, if you use a browser plug-in that automatically expands short URLs, it looks a lot like a human user to an analytics program.
They're all different pieces of the engagement puzzle
Keep in mind that data like clicks are just one part of the analytics you'll use to measure engagement with your content. Bitly link metrics are designed to complement other engagement data.