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Does capitalizing the word “FREE” in title tags increase click through rates?

Posted on May 16, 2024 by Demetria Spinrad

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This week, we asked our Twitter/X and LinkedIn followers what they thought would happen when we capitalized the word “FREE” in a free shipping offer within title tags. Would this change increase click-through rates, leading to a measurable improvement in organic traffic for the ecommerce customer?

Here’s what our followers thought would happen:

Screenshot 2024-05-16 at 08.15.59

We had a perfectly even split from poll respondents this week! Half of our followers thought we'd see a significant increase in click-through rates, but half thought we wouldn't see detectable changes in traffic. Read on to figure out which group was correct.

The Case Study

One of our ecommerce customers wanted to test if capitalizing the word “FREE” to emphasise their free shipping deals in title tags could increase traffic to their brand category pages. By capitalizing certain words, they hoped the change would help catch users' attention and potentially increase click-through rates. Let's explore this strategy and see if it made a positive impact on organic traffic.

We know that although capitalization within title tags is not a direct ranking signal, strategically capitalized words can draw users’ attention amongst crowded search results, making them more likely to click through to a page. In our previous case study on capitalized keywords in title tags, we saw a positive impact on traffic, with an estimated 8.5% increase in organic sessions to the variant pages with their category keywords capitalized. Could capitalizing the word “Free” to “FREE” produce the same results by drawing users’ attention to the value of the free shipping deal?


This experiment produced inconclusive results, with no statistically significant impact on organic traffic.

Several possible factors could have contributed to this inconclusive result. Google often edits the content and capitalization of page titles it chooses to display in search results, so our changes to the title tags may not have been reflected in what users actually saw in the SERPs. It’s also possible that the offer of free shipping wasn’t enticing enough to encourage users to click through to the brand category pages, therefore click-through rates weren’t significantly impacted by the change.

Even though we had seen capitalization in title tags make a big difference in other tests, in this case, we found no detectable impact on organic traffic when we capitalized the word “FREE” to emphasize our customer’s free shipping offer. 

At SearchPilot, we run tests instead of making blanket recommendations because we know that the true SEO impact of changes can be unexpected and differs amongst industries and niches. By iterating on our previous test around capitalization in title tags, we learned that adding a capitalized word to your title tags won’t always lead to an increased click-through rate. We often recommend iterating on results like this to get even more specific learnings about why a change might be impacting your organic traffic.

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How our SEO split tests work

The most important thing to know is that our case studies are based on controlled experiments with control and variant pages:

  • By detecting changes in performance of the variant pages compared to the control, we know that the measured effect was not caused by seasonality, sitewide changes, Google algorithm updates, competitor changes, or any other external impact.
  • The statistical analysis compares the actual outcome to a forecast, and comes with a confidence interval so we know how certain we are the effect is real.
  • We measure the impact on organic traffic in order to capture changes to rankings and/or changes to clickthrough rate (more here).

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