Skip to content Skip to footer
Impression Share Lost to Rank - Marketing Glossary

Impression Share Lost to Rank


Impression Share Lost to Rank (ISLR) is a crucial metric in SEO that measures the percentage of potential impressions lost due to the position of a website’s ranking on search engine results pages (SERPs). It indicates the proportion of times a website could have been shown in search results, but didn’t appear due to its ranking position relative to competitors.

Example of How You Can Use Impression Share Lost to Rank

For instance, if a website has an ISLR of 20%, it means that out of all the potential impressions it could have received, it missed out on 20% due to its ranking position. This suggests that improving the website’s ranking could significantly increase its visibility and traffic.

Calculation of Impression Share Lost to Rank

ISLR can be calculated using the formula:

ISLR=(Total Impression Share/ Lost Impression Share​)×100


  • Lost Impression Share is the percentage of impressions lost due to rank.
  • Total Impression Share is the total potential impressions a website could have received.

Key Takeaways

  1. Performance Indicator: ISLR indicates how well a website’s ranking position aligns with its potential visibility in search results.
  2. Competitive Insight: It provides insights into how a website’s ranking compares to competitors and the impact on potential impressions.
  3. Optimisation Focus: Identifying areas where ranking improvements can lead to increased impression share and traffic.
  4. Benchmarking Tool: Helps set realistic goals and benchmarks for SEO performance improvement efforts.
  5. ROI Measurement: Enables tracking the effectiveness of SEO strategies in improving ranking positions and increasing visibility.


What is Impression Share Lost to Rank?

Impression Share Lost to Rank (ISLR) is the percentage of potential impressions lost due to a website's ranking position on SERPs.

How is ISLR calculated?

ISLR is calculated by dividing the lost impression share by the total impression share and multiplying by 100.

Why is ISLR important in SEO?

ISLR indicates how well a website's ranking aligns with its potential visibility, helping to identify areas for improvement.

What factors contribute to high ISLR?

High ISLR can be attributed to factors such as low-quality content, poor backlink profile, or ineffective keyword targeting.

How can ISLR be improved?

Improving ISLR involves optimizing website content, enhancing user experience, and implementing effective SEO strategies to increase ranking positions.

Does ISLR directly impact website traffic?

Yes, improving ISLR typically leads to increased website traffic as higher rankings result in more visibility and clicks.

Can ISLR be used to measure the success of SEO campaigns?

Yes, monitoring changes in ISLR over time can help assess the effectiveness of SEO efforts and identify areas for further optimization.

Is ISLR the only metric to consider for SEO performance?

No, ISLR should be considered alongside other metrics such as organic traffic, keyword rankings, and conversion rates to gain a comprehensive understanding of SEO performance.

What tools can be used to track ISLR?

Various SEO tools like SEMrush, Ahrefs, and Google Search Console provide insights into ISLR and related metrics.

How frequently should ISLR be monitored?

ISLR should be monitored regularly to track performance trends and identify any fluctuations that may require immediate attention.

Let’s plan your strategy

Irrespective of your industry, Kickstart Digital is here to help your company achieve!

-: Trusted By :-