Google Analytics is the default for acquisition analytics, while PostHog is an open-source product analytics platform that feels closer to a CDP. Both tools can track events, build funnels, and connect to warehouses. But the way they handle identity, data flows, reporting, and customization is radically different.
When teams ask whether they should use GA4, PostHog, or both, the answer depends on how you make decisions and what kind of visibility you need. To make this clear, we’ll break down the comparison into six practical criteria:
- Customization – what you can (and can’t) do when you need something beyond the defaults.
- User Identification – how each platform handles users, IDs, and profiles.
- Data Flows – how data gets in, and how easily it can be exported or activated.
- Reporting – the built-in dashboards and exploratory tools for answering questions.
- Documentation & Updates – how quickly each platform supports you when things change or break.
- Pricing – the real-world cost of running each tool at scale.
TL;DR What to choose between GA4 and PostHog
- If you need marketing attribution + a free baseline: start with GA4 and export to BigQuery for real analysis.
- If you need product analytics + unified profiles + easy outbound actions: go PostHog.
- If you’re serious about decisions: run both in parallel for 30–60 days, align event names, and evaluate with your own data.
How Do PostHog and GA4 Handle User Identification?
The biggest difference between GA4 and PostHog is how they treat users.
In PostHog, every visitor can become a person profile. You can choose to create these profiles only when someone is identified, for example by submitting a form with their email, or for every visitor from the start. Once identified, all anonymous history merges into a single profile tied to their email. That makes it easy to view a timeline of events across multiple sessions and devices, giving you the full picture of a real person.
GA4, in contrast, is anonymous-first. You can assign a User-ID, but you cannot store personal identifiers like email addresses. To unify users across sessions or platforms you need to reconcile User-ID and client IDs inside BigQuery. It works, but it feels less natural in GA4’s interface.
If your work requires knowing exactly who did what, and acting on that information, PostHog is much more effective. GA4 is fine if you only need aggregated insights without direct identity resolution.
How Do You Get Data Into and Out of GA4 and PostHog?
Getting data into GA4 is straightforward for browser events. You can drop the GA4 tag directly on your site or use Google Tag Manager. The challenge comes with server-side events. Google provides the Measurement Protocol, but it is complex and often fragile, making reliable implementation difficult.
PostHog takes a more practical approach. Browser tracking works just as easily, and sending server events is straightforward since you can use an email or user ID as a unifier. APIs and webhooks integrate cleanly, so it feels natural to combine frontend and backend data in the same platform.
When it comes to exporting data, GA4 is focused on the Google ecosystem. You can link GA4 to Google Ads, Search Console, and BigQuery. BigQuery is the real power option, but everything still lives inside Google’s garden. PostHog is more open. It integrates with Slack, Zapier, HubSpot, Snowflake, Redshift, Postgres, Customer.io, and many others. This makes PostHog closer to a lightweight CDP, where you can send data anywhere it is needed for action.
Which Reporting Features Are Better: GA4 or PostHog?
GA4 organizes reporting into two main areas. The first is Reports, which include standard views like acquisition, engagement, and conversions. These can be customized, but only to a certain extent. The second is Explorations, which are designed for deeper analysis such as funnels, pathing, and segment overlaps. Explorations are powerful but often hard to share across teams, and many organizations end up exporting data to Looker Studio or BigQuery for consistent reporting.
PostHog uses a different structure with Insights and Dashboards. Insights cover funnels, retention, paths, and trends. Dashboards allow you to group these insights in ways that make sense for different teams. Funnels in PostHog are flexible, allowing sequential or non-sequential steps, breakdowns, and filters that make analysis easy to explain to stakeholders.
If your focus is attribution and acquisition marketing, GA4 reports feel natural. If your focus is product usage, lifecycle, and retention, PostHog’s dashboards and funnels are faster and more intuitive.
Which Platform Has Better Documentation and Updates?
Documentation and updates reflect the culture of each platform.
GA4 has documentation spread across official Google sites, help articles, and community forums. Updates are frequent but often disruptive. For example, recent changes to how cookies and sessions are handled broke many implementations, and Google only announced the update after the fact. Debugging in GA4 often requires digging through BigQuery or searching community discussions.
PostHog, by contrast, is highly transparent. Product updates are published frequently, documentation is clear and practical, and multiple methods are offered for achieving the same outcome. Debugging is easier because you can trace events to person profiles directly in the UI and validate flows in real time.
For teams that value speed, clarity, and transparency, PostHog is significantly easier to work with.
What Are the Real Costs of Using GA4 vs PostHog?
GA4 is free in its standard edition, but that does not mean there are no costs. Once you start exporting data into BigQuery you will pay for storage and queries. If you need GA4 360, pricing moves into enterprise levels that start in the thousands of dollars per month.
PostHog offers a generous free tier of one million events per month. Beyond that, pricing is usage-based. You pay per event, and you can add optional features such as session replays, feature flags, or warehouse sync. For example, tracking 30 million events per month might cost under one thousand dollars depending on your setup. The model is transparent, and you can always downsample noisy events to control costs.
If minimizing cost is your only goal, GA4 is the clear winner. But if you want data ownership and downstream actionability, PostHog justifies its price for most product-led teams.
How Customizable Are PostHog and GA4?
Customization is one of PostHog’s strongest points. Because it is built on ClickHouse, you can write SQL-like queries directly inside the platform, materialize views, and visualize results without leaving the UI. PostHog also offers an AI assistant called Max that can generate queries against your schema. This makes advanced analysis more accessible and faster.
GA4 does not offer the same level of customization in its interface. For true flexibility you need to export data into BigQuery and build your own queries and dashboards in Looker Studio or another BI tool. This is powerful, but it splits workflows between analysts in BigQuery and marketers inside GA4.
If you want rapid iteration in one place, PostHog is the better choice. If your organization already relies on a BI-first workflow with BigQuery, GA4 fits neatly into that system.
What Extra Features Does PostHog Offer Beyond GA4?
PostHog positions itself not only as an analytics tool but as a full product growth platform. In addition to tracking and reporting, you can enable session recordings to watch real user interactions, launch feature flags to control rollouts, run A/B tests and experiments, and even monitor error tracking within the same system. It also includes surveys and feedback tools to connect quantitative data with qualitative insights.
GA4, in contrast, focuses purely on analytics. For experiments, session replays, or error tracking, you would need to integrate third-party tools.
Which Analytics Tool Should You Choose for Your Business?
The answer depends on your priorities. If your main concern is attribution and acquisition reporting, GA4 remains the default option, especially because it is free. If your team is focused on product usage, retention, and lifecycle questions, PostHog is far more intuitive and actionable.
In practice, many organizations benefit from running both tools side by side. By aligning event names, exporting data to a warehouse, and comparing results for thirty to sixty days, you can see which tool your team opens every morning. That is usually the one that will deliver the most value in the long run.
Quick Comparison Table: PostHog vs. GA4
| Dimension | GA4 (Google Analytics 4) | PostHog |
|---|---|---|
| User Identification | Anonymous-first; User-ID allowed but no PII | Person profiles tied to email or IDs; merges anonymous & identified |
| Data Ingestion | Easy browser setup; server events via fragile Measurement Protocol | Browser + API + webhooks; email unifier makes backend events clean |
| Data Export | Ads, Search Console, BigQuery (all Google-owned) | Wide range: Slack, Zapier, HubSpot, DBs, CDPs, feature flags |
| Reporting | Standard Reports + Explorations; deeper analysis in BigQuery | Insights + Dashboards; flexible funnels, paths, retention |
| Docs & Updates | Documentation scattered; updates often break things without notice | Transparent, frequent updates; clear debugging flows |
| Pricing | Free standard; GA4 360 is enterprise-only; BigQuery costs extra | Free 1M events/month; pay-as-you-go beyond that, add-ons optional |
| Customization | Limited in UI; real power in BigQuery + BI | SQL & ClickHouse queries in-platform; AI-assisted analysis |
Common questions about PostHog vs. Google Analytics
Is PostHog better than GA4?
It depends on your goals. GA4 is excellent for marketing attribution and acquisition reporting, especially if you already use Google Ads and BigQuery. PostHog is stronger for product analytics, user journey tracking, and lifecycle questions. Many teams use both.
Can PostHog replace Google Analytics?
PostHog can replace GA4 if your focus is product analytics, retention, and experiments. However, GA4 remains useful for acquisition metrics and marketing attribution, which PostHog does not cover as deeply.
Does PostHog have features GA4 does not?
Yes. PostHog offers session recordings, feature flags, A/B testing, error tracking, and surveys, making it a full product growth platform. GA4 is strictly an analytics tool and requires third-party integrations for these features.
Is PostHog free to use?
PostHog has a free tier of one million events per month. Beyond that, pricing is pay-as-you-go based on events and optional add-ons such as session replays and feature flags.
How much does GA4 cost?
GA4 is free in its standard version. Costs arise when you export data to BigQuery, where you pay for storage and queries. GA4 360, the enterprise version, costs thousands of dollars per month.
Should I use both GA4 and PostHog?
Yes, many organizations run GA4 and PostHog side by side. GA4 provides free marketing attribution, while PostHog offers actionable product analytics. Running both in parallel for 30 to 60 days helps you decide which tool your team will rely on most.
