What Is Session Replay

28 October 2022

Session replays are videos of user activity on your website or app. Unlike regular videos, session replays contain rich information on exactly what your users did including button clicks, pages visited, data on errors, console logs and much more.

This ultimate guide to session replays will cover everything you need to know starting from how session replays work and privacy considerations through to feature sets and choosing the best session replay tool.

How Do Session Replays Work?

Websites are fundamentally built using 3 components, namely HTML, CSS and JavaScript. When your web browser displays a site to you, it does so by constructing a document object model (DOM) which is a tree like structure representing all the elements on the site. These elements include everything from buttons and images through to links and text fields.

Session replays work by recording a log of the initial DOM as well as all changes (referred to as mutations) to the DOM. Good session replay tools also record the CSS (styling) and Javascript from the website.

When a session replay is played back at a later point in time, each log entry is replayed so that it looks like a video but is actually much more than that because you have access to all the rich underlying log data.

Are Session Replays And Screen Recordings The Same Thing?

Session replays and screen recordings are not the same thing. Session replays are created by logging every action on a website including those that you aren't able to see while screen recordings simply record a video of the screen.

Imagine someone stood next to you with a video camera and recorded your screen while you browsed around a website. This would be similar to the concept of a screen recording.

Now imagine there was a robot sitting inside the website writing down everything that happens on a website. Every time a button is clicked, the robot writes it down. Every time text is entered, the robot writes it down. Every time an error occurs which you might not be aware of, the robot writes it down. And so on.

When it comes time to watch the session replay at a later stage, the robot stitches together everything that happened on your website by reading through all the log entries.

Due to the rich underlying information available to you, session replays are generally superior to screen recordings when it comes to customer support, product development and several more use cases which we discuss below.

What Information Is Available In A Session Replay?

Websites are dynamic and complex. Recording every aspect of a website is no simple task.

Here's a list of the things which session replay tools aim to record:

  • The entire HTML DOM (document object model)
  • CSS styling and animations
  • SVG's and vector graphics
  • Mouse movements, clicks, scrolling and hovering effects
  • Text input and typing
  • Embedded <iframe> elements
  • Window resizing
  • Page navigation both across regular websites and SPA's (single page apps)
  • HTML5 <audio> and <video> playback
  • Web components and shadow DOM
  • Programmatic updates (eg: javascript which has an effect on the website)
  • All of the above when rendered on any device (eg: desktop, laptop, mobile)

With all this information at your finger tips, it's no wonder session replays are superior to screen recordings.

Will Session Replays Slow Down My Website?

The answer to this depends on which session replay tool or service provider you choose.

At Feederloop, we take care at every level of our technology stack to ensure our session replay tool has no impact on the performance of your website.

We use a variety of cutting edge techniques to optimise performance, reduce load time, offload main thread work and batch network requests.

However it's important to know that not all providers take the same level of care in this respect.

How Do Session Replays Help Your Business?

In short, session replays help you provide better support to your customers while building a better, more engaging product.

Here's a list of specific benefits to using session replays in your business:

Understand And Improve User Experience

No matter how much care and effort you put into creating your website or app, it's hard to know if end users ultimately find the experience intuitive and enjoyable to use.

UX designs and navigation that makes perfect sense to your developers and designers might be frustrating or overly complex for your users. Tools like Google Analytics can't help with this. It can't show when a user is confused or when they interact with your site in a way that you didn't expect.

Session replays help your business:

  • Identify bad or unintuitive UX designs.
  • Identify confusing navigation where users are unable to find what they're looking for.
  • Ensure users understand how to use your product across mobile and desktop layouts.

Conversion Rate Optimization

To make the most of incoming website traffic you need to ensure your website is optimised for converting leads into paying customers. This involves ensuring your website is both intuitive and informative while being clear about call to actions and next steps.

Session replays help answer conversion related questions such as:

  • Are users getting confused or frustrated?
  • Are users not seeing the call to action (CTA) on a specific page? Maybe they scroll right past it?
  • Are users not engaging with the UI in a way you expected, resulting in poor conversions?

Efficient Customer Support

Traditional online customer support often involves asking for screenshots with a lot of back and forth questions while trying to understand exactly what the issue is. An issue can only be resolved by a customer service agent once they fully understand it.

Session replays reduce this time drastically by cutting out the need for excessive questions and screenshots. By watching a real time or historical session replay, customer service agents immediately understand what the issue is allowing them to resolve it faster.

Understand And Improve Onboarding Flows

Once a prospect converts to a customer, a smooth and informative onboarding process is key to them getting early value from your product and ultimately increasing engagement.

By analyzing session replays for user onboarding, you'll be in a position to optimize the journey while ensuring new customers understand how everything works.

Session replays can also provide excellent insight into internal staff onboarding. By understanding staff onboarding to internal apps, you can reduce the time it takes them to get up and running.

Understand And Improve Feature Adoption

With all the planning, development and time it takes to implement and roll out new features it's important to understand how well they're adopted by your user base.

Session replays help you understand how users interact with new features. They answer questions like "Is the feature being used as we expected?" and "Is the feature intuitive?".

Armed with rich insight into how new features are used in the wild, you'll be in a better position to improve adoption and ultimately ensure the success of new releases.

Improve CSAT

A customer satisfaction (CSAT) score measures how satisfied customers are with a purchase, interaction or company. Improving your CSAT over time is crucial to the health of your business.

By leveraging session replays you'll improve your product, understand and improve feature adoption, fix issues quickly and provide proactive customer support. All of these add up to creating a product and company which customers love and forms the basis for ensuring a high CSAT score.

Reduce MTTI and MTTR

Technical teams often track mean time to identify (MTTI) and mean time to resolve (MTTR) when investigating and fixing bugs. Empowering your developers with session replays lets them watch exact replays of bugs as they occur in the wild.

Rather than trying to explain a customer issue to your developers over email or via screen shots, simply send them a session replay. They'll have everything they need to reproduce and fix the issue without the frustrating back and forth which is usually needed.

Privacy And Protection Of Personal Information

Session replay tools offer a variety of privacy related functionality to ensure personal information is protected. When deciding on a session replay tool it's important to understand what it offers in terms of privacy protection.

Here are a few items to be aware of when dealing with the protection of personal information (PPI) in the context of session replay tools:

  • Session replays can only be created on web pages where the tool is installed. This means session replay tools can't track you across the internet. This is in contrast to analytics tools like Google Analytics which can and do track you across the internet.
  • There should be the option to mask or hide text input fields. This could be done in a number of ways including masking everything or specifying specific fields to be masked. Feederloop opts for a privacy first stance where all text inputs are masked by default. Alternatively Feederloop lets you conditionally mask specific fields if you prefer.
  • Privacy policies should include information stating that session replays are being used along with specifics on exactly what personal information is stored.

Do You Need On Demand, Sampling Or All Session Replays?

There are generally 3 approaches to the frequency of recording session replays:

  1. Record everything: With this approach, every single session is recorded. This means every time someone visits your website their entire journey through your site is recorded. As you might imagine, this can result in a massive amount of data.
  2. Sampling: With this approach, a certain percentage of all sessions are recorded. For example a random 50% of all sessions might be recorded.
  3. On Demand: With this approach, you have the option to specify which sessions should be recorded. For example if you notice a customer having an issue with something, you can flag that session to be saved.

So the obvious question at this point is, which option is best? Well there's no one size fits all.

Your first instinct might be to simply record everything. However this typically results in far too many sessions to ever make use of. Just imaging that your website has a modest 100 visitors per day. The record everything approach would result in 700 recordings a week and roughly 3 000 recordings per month. With that many recordings they typically become useless and have no meaning.

If your goal is to garner a wide understanding of general user behaviour, then sampling may be the way to go. If your goal is to leverage session replays in a customer support context to help resolve issues and improve your product, then on demand is the way to go.

With Feederloop's focus on improving customer support for both agents and users alike, we provide an on demand approach.

What Should You Look For In A Session Replay Tool?

Session replay tools can be used for a wide variety of use cases which results in different feature sets and abilities. However with that in mind, here are several key factors which you should ensure are available:

Is CSS Cached?

As we discussed earlier in the article, websites are fundamentally built using 3 components, namely HTML, CSS and Javascript. As websites change over time, those building blocks change. For session replays to work correctly when watching old versions of your website, the assets used at that point in time must have been cached.

Be sure to check that your session replay tool of choice caches CSS when creating recordings. If that doesn't happen, your old session replays won't work correctly when changes are made to your website.

Can You Mask Private Information?

As discussed in the Privacy And Protection Of Personal Information section, it's important that your session replay tool of choice takes privacy seriously.

There should be options to mask all text inputs or conditionally mask specific inputs. Your user's personal information should be kept private at all times.

Is Multi Page Recording Supported?

When a user navigates between multiple pages on your website, session replay tools should be able to follow that journey and record it seamlessly. The last thing you want is for a user to navigate to 10 different pages which results in 10 different recordings. In a case like that, there should only be one recording following the user's journey through your site.

Does It Work On Static HTML Websites and Single Page Apps

A single page app (SPA) is an alternative to traditional websites where each page is retrieved from a server on demand. In the case of SPA's, the entire website (or specific chunks of it) are downloaded in one go. This means as you navigate to new pages, there aren't necessarily any additional calls to a server to retrieve the new page.

SPA's are particularly popular when used to create web apps for SaaS (Software as a Service) companies. Because of this, Feederloop works seamlessly on all websites regardless of how they're built.

Is There An Impact On Website Performance

The performance impact on your website depends on how the session replay tool has been implemented and the level of care taken around resource usage.

Feederloop uses a variety of cutting edge techniques to optimise performance, reduce load time, offload main thread work and batch network requests. Thanks to this, our customers experience no performance impact on their websites.

Real Time vs Historical Replays

Historical session replays are probably the most common. This is where all sessions (or a sample) are recorded. You then login to the session replay tool to find thousands of recordings ready to watch.

Real time replays (such as those provided by Feederloop) allow you to watch users in real time as they browse your website and then save the recordings when you choose to. This approach is invaluable in the customer service space where agents assist customers in real time when they have questions and then save the recordings if needed. Session replays can then be shared with developers or product teams.

Is Searching And Filtering Available?

Given the sheer volume of session replays which can potentially be generated, especially if you're not using sampling or on demand recording, it's important that robust search and filtering is available.

How Long Are Session Replays Stored For?

Generally speaking, session replay tools don't usually store your recordings forever. Data retention is often limited to a certain number of weeks or months.

Depending on how far back you want to look, it might be important for you to choose a tool that provides a longer data retention period.

How Many Session Replays Are Allowed?

This is closely tied to the question of data retention duration. In this case however, we're looking at how many simultaneous replays are allowed.

Generally speaking, you wont be able to store an unlimited number of session replays. The exact number differs across providers.

On Demand vs Sampling vs Everything

As discussed above, the choice between on demand, sampling or recording everything often comes down to your use case.

Recording everything may be useful in cases where you want to generate aggregated insights. On demand is useful in customer support contexts when coupled with real time agent support.

Is It Easy To Implement?

The underlying technology of a session replay tool can be quite complex however you should choose a tool which hides that complexity from you by providing an easy installation process and intuitive UI/UX in the tool.

Some tools require several days/weeks coupled with support from experts to install and setup. Feederloop on the other hand is installed in a few minutes by adding a single script tag to your website.

Are Additional Insights Available?

A large part of the benefit to using session replays over screen recordings is all the rich underlying data and insights that can be surfaced. You should choose a tool that leverages that potential by showing you additional information such as console logs, errors, pages visited etc.

Which Job Roles Benefit From Using Session Replays?

If used right, session replays are an invaluable tool across the business. Here are a few specific business areas which often benefit from session replays:

Product Teams

It's no secret that software engineers are expensive. Typical bug reports sent to developers over email or screenshots result in a lot of wasted time just to reproduce the issue before even starting to fix it.

By sending bug reports to developers in the form of session replays, you'll drastically cut down the time it takes to implement fixes.

A common pattern we see at Feederloop is for customer support agents to assist users in real time (via voice/video chat and co-browsing) while recording the session. If the agent is unable to assist the user because the issue they're facing relates to a bug, they simply send the session replay to the development team.

Designers and UX Teams

No matter how much care and attention has been put into the UI/UX of your product, it's still likely to result in unexpected user behaviour out in the wild.

To constantly iterate and improve your UI/UX, it's critical that designers are able to watch session replays to understand how users actually engage with your website or app. Aspects of your UI which seemed incredibly intuitive in-house might result in confusion or frustration by your user base. Without using session replays, you would never realize this.

Customer Support Teams

Customer support agents gain additional context about user issues and are in a better position to help when they leverage session replays. By seeing exactly what users are struggling with, it's far easier for agents to understand and resolve queries quickly.

Feederloop even takes this a step further by allowing agents to co-browse or have a video chat with customers in real time while watching their session.

Marketing Teams

Session replays provide marketers with qualitative information that's difficult to obtain in any other way. By analyzing session replays of A/B tests, changes to marketing copy or design elements, marketers are able to further improve conversion rates.


Hopefully this ultimate guide to session replays has given you the information you need to both understand what session replays are and to find a solution that suits your use case.

While many solutions focus solely on session replays, there are those such as Feederloop which go further by providing real-time session watching, video chat and co-browsing all bundled into a single solution. If you're interested in finding out how Feederloop's suite of products could potentially help your business, please reach out any time.