It’s been a point of contention for some time now: just how much traffic does Twitter actually drive to your site? The general thought is “probably more than you think,” as web analytics tools are apt to under-report your Twitter referrals.

Why? Basically, because Twitter’s API gives access to so many different third-party apps and various other social sites. Many of your referrals that are actually coming in by way of Twitter might not show up as referrals from Twitter.

A study we reported on in July found that only 24.4% of clicks on links shared on Twitter actually had twitter.com as the referring site. 13% of clicks from Twitter had another site as the referrer like Facebook or LinkedIn. And 62.6% of clicks from Twitter didn’t have any referral information at all.

In a nutshell, Google analytics might be listing your traffic from Twitter as traffic from Facebook or direct traffic or a number of other things.

A few months ago, Twitter announced that all links shared on Twitter.com as well as through third-party apps using Twitter’s API would contain a special t.co URL. In theory, this helps referrals from Twitter actually show up as referrals from Twitter.

Today, Twitter is doing more to ensure that you know exactly what you’re getting from their service. They have announced Twitter Web Analytics, an analytics tool “driven by the acquisition of BackType” (BackType is a social analytics startup that Twitter snatched up back in July).

Twitter is a powerful platform for websites to share their content, and drive traffic and engagement. However, people have struggled to accurately measure the amount of traffic Twitter is sending to their websites, in part because web analytics software hasn’t evolved as quickly as online sharing and social signals.

The tool will let you see the amount of traffic being sent toy your site by Twitter referrals, let you “understand how much your website content is being shared across the Twitter network,” and also gauge just how effective that Tweet Button on your site really is.

With the tool, you can also see your most-shared links by day, week or month – either based on Tweets or by clicks.

The tool will be rolled out to a small test group this week and will go public in the next few weeks. An API is also on the way, although no specific timeframe was announced.