Deploying a reverse proxy to PostHog Cloud

A reverse proxy enables you to send events to PostHog Cloud using your own domain.

This means setting up a service to redirect requests from a subdomain you choose (like e.yourdomain.com) to PostHog.

You then use this subdomain as your api_host in the initialization of PostHog instead of us.i.posthog.com or eu.i.posthog.com.

Why do we recommend deploying one?

Using a reverse proxy means that events are less likely to be intercepted by tracking blockers.

You'll be able to capture more usage data without having to self-host PostHog, ensuring you get a complete view of your users.

Deploying a reverse proxy

Using our managed reverse proxy is the easiest way to do this.

It's available as part of our platforms add-ons, which includes automatic provisioning, SSO and 2FA enforcement, priority support, and additional collaboration features.

Other documented options for deploying a reverse proxy include:

• AWS CloudFront
• Caddy
• Cloudflare
• Kubernetes Ingress Controller
• Netlify
• Next.js rewrites
• Next.js middleware
• nginx
• Remix
• SvelteKit
• Vercel
• Nuxt
• Pomerium

Best practices

• We require that the proxy sets the Host header to the same host it's calling. Check the guides above on how to do that for several proxies.
• Don't use a subdomain that includes posthog, analytics, tracking, or other similar words which might cause events to be blocked.
• Make sure to pass the proper ui_host parameter when initializing PostHog, so that links to PostHog point to the correct host (like us.posthog.com). This is required for tasks like authenticating the toolbar.

• Avoid using generic or common path names like /analytics, /tracking, /ingest, or /posthog for your reverse proxy. They will most likely be blocked. Instead, use a non-obvious path name or something random and unique to your application that's unlikely to appear in a filter list.

Reverse proxy requirements

If you want to use an alternative reverse proxy that we have not documented, it must meet the following requirements:

- route: e.yourdomain.com/static/*
  reverse_proxy: https://us-assets.i.posthog.com/static/*
  host_header: us-assets.i.posthog.com

- route: e.yourdomain.com/*
  reverse_proxy: https://us.i.posthog.com/*
  host_header: us.i.posthog.com