---
title: PostHog (open source)
description: Product analytics, session recordings, feature flags, and A/B tests in one platform, with an open-source core.
canonical: "https://10xgtm.ai/oss/posthog"
type: open-source-review
license: MIT (ee/ proprietary)
repo: "https://github.com/PostHog/posthog"
language: Python
---

# PostHog

Product analytics, session recordings, feature flags, and A/B tests in one platform, with an open-source core.

The most complete open-source analytics stack: funnels, session recordings, feature flags, experiments, and surveys share one system, so product-led GTM teams stop stitching five vendors together. The catch is that the self-hosted free build is deliberately limited, and serious volume pushes you to their paid cloud.

## Project facts

- **License:** MIT (ee/ proprietary)
- **Repo:** https://github.com/PostHog/posthog
- **Stars:** 38.1k
- **Language:** Python

## What it does

- Funnels, retention, trends, and cohorts that show where visitors convert and where they abandon
- Session replay recordings, so you watch real users get stuck instead of guessing from charts
- Feature flags that switch features on for selected segments and roll them back instantly
- A/B testing with clear statistical readouts, so page and onboarding changes get measured properly
- Surveys, error tracking, and imports from tools like Postgres and BigQuery
- An AI assistant that answers questions in plain language, builds dashboards, and helps debug broken tracking

## What it can't do

- Match its own cloud product when self-hosted; the free build is not meant for high-volume production use
- Claim fully open licensing; some enterprise features are proprietary and stripped from the public mirror
- Run lightly; self-hosting requires serious backend machinery and a real IT commitment
- Do marketing attribution or ad-spend ROI end to end; it tracks product behavior, not campaign performance
- Load invisibly; its tracking code can slow page load when installed early, especially with recording on

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Full review: https://10xgtm.ai/oss/posthog