Session replay installation

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Session replay enables you to record users navigating through your website and play back the individual sessions to watch how real users use your product.

Above is a recording of posthog.com… on posthog.com – very meta.

Step one: Install our JavaScript web library

Option 1: Add JavaScript snippet to your HTML Recommended

This is the simplest way to get PostHog up and running on your website, and only takes a few minutes to set-up.

Add to your website & app

Paste this snippet within the <head> tags of your website - ideally just inside the closing </head> tag - on all pages that you wish to track.

HTML
<script>
!function(t,e){var o,n,p,r;e.__SV||(window.posthog=e,e._i=[],e.init=function(i,s,a){function g(t,e){var o=e.split(".");2==o.length&&(t=t[o[0]],e=o[1]),t[e]=function(){t.push([e].concat(Array.prototype.slice.call(arguments,0)))}}(p=t.createElement("script")).type="text/javascript",p.async=!0,p.src=s.api_host+"/static/array.js",(r=t.getElementsByTagName("script")[0]).parentNode.insertBefore(p,r);var u=e;for(void 0!==a?u=e[a]=[]:a="posthog",u.people=u.people||[],u.toString=function(t){var e="posthog";return"posthog"!==a&&(e+="."+a),t||(e+=" (stub)"),e},u.people.toString=function(){return u.toString(1)+".people (stub)"},o="capture identify alias people.set people.set_once set_config register register_once unregister opt_out_capturing has_opted_out_capturing opt_in_capturing reset isFeatureEnabled onFeatureFlags getFeatureFlag getFeatureFlagPayload reloadFeatureFlags group updateEarlyAccessFeatureEnrollment getEarlyAccessFeatures getActiveMatchingSurveys getSurveys".split(" "),n=0;n<o.length;n++)g(u,o[n]);e._i.push([i,s,a])},e.__SV=1)}(document,window.posthog||[]);
posthog.init('<ph_project_api_key>', {api_host: '<ph_instance_address>'})
</script>

Be sure to replace <ph_project_api_key> and <ph_instance_address> with your project's values. (You can find the snippet pre-filled with this data in the PostHog app under Project / Settings. (Quick links if you use PostHog Cloud US or PostHog Cloud EU)

What this code does

After adding the snippet to your website, it will automatically start to:

Option 2: Install via package manager

yarn add posthog-js

And then include it in your files:

Web
import posthog from 'posthog-js'
posthog.init('<ph_project_api_key>', { api_host: '<ph_instance_address>' })

If you don't want to send a bunch of test data while you're developing, you could do the following:

Web
if (!window.location.host.includes('127.0.0.1') && !window.location.host.includes('localhost')) {
posthog.init('<ph_project_api_key>', { api_host: '<ph_instance_address>' })
}

If you're using React or Next.js, checkout our React SDK or Next.js integration.

Step two: Enable session recordings in your project settings

Enable session recordings in your PostHog Project Settings.

Enable session recordings in your PostHog

Once enabled, the library will start recording sessions by default.

They can be toggled off in the by setting the disable_session_recording: true flag in the config.

Users who opt out of event capturing will not have their sessions recorded.

Note on using Segment's SDK: Session Replay does not work if you send data using Segment's SDK as this data is not collected. If you use Segment, you may want to add the PostHog library as well – (make sure to only send regular event data from one source).

How to ignore sensitive elements

You may want to hide sensitive text or elements in your replays. See our privacy controls docs for how to do this.

Questions?

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How to watch recordings

To watch recordings, you can visit the Replay page. When watching replays, you can change the playback speed, as well as select the option 'skip inactivity' - this skips parts of the recording where the user was inactive on the page. You can also watch recordings by clicking on any data point in an insight. This opens a list of persons and displays a "watch recording" button if available. This is especially useful in funnels , where you can drill down and watch recordings of users who…

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