This article will help you:
  • Learn how Optimizely Web Experimentation and Full Stack calculate results to enable business decisions
  • Determine the definitions and formulas for result metrics
  • Share the results of your experiments with others
  • Export campaign or experiment results in a comma-separated value (CSV) format

The Results page at a glance

Optimizely's experiment Results page helps you measure success in an experiment. Dive into each metric and variation to see how visitors respond to changes you made to your site.

Key tips

What to watch out for

  • If you add more than five metrics to an experiment, the additional metrics may take longer to reach statistical significance
  • Visitors are bucketed into variations by chance according to the traffic distribution percentage you set, so you may not see the exact same number of visitors in each variation

Optimizely's experiment Results page is powered by Stats Engine. It provides a data-rich picture of how your visitors interact with your site. Use it to measure success in an experiment and learn about visitors to your site. In Optimizely, the experiment Results page includes confidence intervals and incorporates a Stats Engine improvement that reduces the false discovery rate.

This article walks through the experiment Results page for Optimizely Web Experimentation. If you're using Optimizely Web Personalization, there's a slightly different Results page. You can also check out our Optimizely Academy course, Information on the Results Page.


Here's what you'll see in the left-hand navigation: 

  • Options to pause, preview, or archive the experiment

  • The date when changes were last published

  • Number of days running (Looks at the exact times an experiment was started/stopped and represents the number of full days an experiment is/was running. Floating numbers are truncated rather than rounded up so i.e. 17.8 becomes 17.)

  • Audience(s) targeted in the experiment

  • Pages included in the experiment

  • Number of visitors

The summary and metric modules provide an in-depth view of your visitors' behavior on your site. We'll discuss those below. You can also learn how to interpret the results you see in Optimizely.

All results in Optimizely are in local time, according to the time zone set on your machine.

Results are typically available within 5 to 10 minutes of Optimizely receiving the data. Read our article about data freshness to learn more.

Find the experiment Results page

Here are two ways to find the experiment Results page:

  • Experiments dashboard > Results

  • Manage Experiment dashboard > View Results


The experiment Results page provides a high-level summary and a module for each metric attached to your experiment. We'll walk through the summary and modules below. You'll use them to check which variations are winning, losing, or inconclusive.


The summary provides a high-level overview of the experiment. It allows you to compare how each variation is performing for the primary metric, compared to the original.

Here's what you see once visitors enter your experiment:


Optimizely shows the number of unique visitors who've been bucketed into each variation.

Above, 423 visitors (or 32.59% of visitors in this experiment) have seen the original variation, 410 (31.59%) have seen Variation #1, and 465 (35.82%) have seen Variation #2.


Below the summary, you'll see results for each metric that you added to your experiment. The primary metric is always at the top.


  • Unique Conversions or Total Conversions: When you add a metric to an experiment, you'll choose unique or total conversions. Unique conversions show deduplicated conversions, so a single visitor who triggers the same event multiple times is counted just once. Total conversions show a simple total of conversions for the event.

  • Conversion Rate or Conversions per Visitor: Under the Unique conversions view, Optimizely shows the conversion rate: the percentage of unique visitors in the variation who triggered the event. Under the Total conversions view, you'll see Conversions per Visitor: the average conversions per visitor, for visitors in the variation.

  • Improvement: For most experiments, Optimizely displays the relative improvement in conversion rate for the variation over the baseline as a percentage. For example, if the baseline conversion rate is 5% and the variation conversion rate is 10%, the improvement for that variation is 100%. The only exception to this is any experiment where Stats Accelerator is turned on: these experiments show absolute improvement instead. 

  • Confidence interval: The confidence interval measures uncertainty around improvement. Stats Engine provides a range of values where the conversion rate for a particular experience actually lies. It starts out wide -- as Stats Engine collects more data, the interval narrows to show that certainty is increasing.

    Once a variation reaches statistical significance, the confidence interval always lies entirely above or below 0.

Statistically significant and positive Statistically significant and negative Not yet conclusive
  • Statistical significance: Optimizely shows you the statistical likelihood that the improvement is due to changes you made on the page, not chance. Until Stats Engine has enough data to declare statistical significance, the Results page will state that more visitors are needed and show you an estimated wait time based on the current conversion rate.

To learn how to capture more value from your experiments, either by reducing the time to statistical significance or by increasing the number of conversions collected, see our article on Stats Accelerator.

Filter experiment results

Use graphs, date range, attributes, and the baseline to dig into results. We'll show you how below.


You can toggle between different graphs for each metric. To see or hide graphs, click Hide graph or Show graph.


  • Improvement over Time (the default): Improvement in this metric for each variation, compared to the baseline

  • Visitors over Time: Total visitors for the variations and the baseline

  • Conversions over Time: Conversions per day in this metric for each variation, including the original

  • Conversion Rate over Time: The cumulative conversion rate for each variation, including the original

  • Statistical Significance over Time: Cumulative statistical significance for the variation

Filter by date range

Use the Date Range dropdown to select start and end dates for your Results page view. Then, click Apply. The results generated will be in your computer's timezone.


Segment experiment results

By default, Optimizely shows results for all visitors who enter your experiment. However, not all visitors behave like your average visitors. Segmenting your results is a powerful way to gain deeper insights about your customers to design data-driven experiments and personalization campaigns. 

Use the Segment dropdown to drill down into a segment of your visitors. You can segment by a single attribute value, or by a combination of attribute values (learn more about using combinations).


For Optimizely Web Experimentation, the default segments are:

  • Browser: Firefox, Google Chrome, Internet Explorer, Opera, Safari, Unknown

  • Source: Campaign, Direct, Referral, Search

  • Campaign

  • Referrer

  • Device

You can also segment by up to 100 custom attributes in Optimizely Web or Optimizely Full Stack.

Change the baseline

Sometimes, you may want to see how all your variations compare to one variation in particular -- which may not be the original. Use the Baseline dropdown to select a different variation as the baseline.


Share experiment results

Use the Share feature to send your Results page to key stakeholders. Click Share and copy the URL provided.


The Share link provides access to the Results page for that specific experiment. Users can segment data, view charts, filter by data range, and more. However, they can't navigate out of the specific experiment or campaign.

If you'd like to reset the link that you shared, click Reset Link. Users with the previous link will no longer have access to the Results page.

Export experiment results data

Use the Export CSV feature to download the results of your experiment in a comma-separated value (CSV) file. You can use this file to view your results data in your favorite spreadsheet program. You can also share the raw results with others, store the data on your own machines, or perform additional analysis.

Click Export CSV to download the CSV file of the results being shown on the page (limited to the Date Range and Segment selected).


Here's a reference list of columns in your exported CSV files and their meanings. You can also access your Optimizely raw data via our Amazon S3 bucket.

Manage metrics

Click Manage Metrics to add or remove metrics, or set a new primary metric. 


Remember, if you add more than five metrics to an experiment, the additional metrics will take longer to reach statistical significance. This is because Optimizely's Stats Engine controls the false discovery rate of your experiment, which is a description of the chances of making an incorrect business decision based on your results. 

However, the additional metrics don't slow down the speed of your overall test. Stats Engine ensures that the primary metric (which signals whether a variation "wins" or "loses") always reaches significance as quickly as possible.

Set currency symbols

You can change the currency symbols displayed for revenue metrics via the Currency Picker that is located under the Advanced tab in the Project Settings:


Note that changing the currency symbol does not convert revenue values based on an exchange rate, it only changes the symbol displayed. So a revenue value displayed as $100.00 would become ¥100 after picking "¥", regardless of the current exchange rate between USD and JPY. Learn more about tracking revenue in Optimizely.

The currency symbol setting you select will be remembered for all sessions on your current browser. This means you will need to set the symbol again when logging in from a new device or browser.

Edit experiment

Click Edit Experiment to make changes to your experiment. Use this option to pause a variation or adjust your traffic distribution.


Reset results

The Reset Results button allows you to reset your Results page. This affects the data displayed on the results page, as well as what is calculated by Stats Engine for this experiment.

The raw data for your experiment will still be available after the reset. If you need to access it, use the Data Export feature. This will allow you to programmatically access your Optimizely raw data via an Amazon S3 bucket. Data will be available on a 30 day rolling basis. 


Once you click on the Reset Results button, a modal will pop up. This modal is an agreement to ensure that you understand that this is a permanent action for the results page. It will also protect against accidentally enabling resets.


Once you check all three boxes, the modal's Reset Results button will become clickable. This is indicated by the color of the button turning from gray to red. 


Clicking on the modal's Reset Results button will close out the modal. You may need to refresh the page to see your change reflected. The results page should now appear as though the experiment has just been started and there is no data yet. All visitor counts, experiment duration, and metrics should go back to displaying 0. There will now be a notation above the Reset Results button that will show the date of the last reset, and the Date Range should only show for the current date. 

Resetting the results does not reset variation bucketing assignments. Resetting the results is purely a front-end "wipe", and as stated above the underlying raw data events for the past results are still available through data exports. When the Results are reset visitors will continue to see the Variation they were previously bucketed into and be counted towards the correct variation.