Auth, email and analytics

Plausible vs Fathom vs PostHog vs Google Analytics 4: website analytics compared

Stack Founder HQ · Updated 18 October 2026 · Auth, email and analytics · How we write

"Analytics" covers two quite different jobs. Website analytics tells you how many people visit, where they come from and which pages they read. Product analytics tells you what signed-in users do inside your app: which features they use, where they drop out of a sign-up flow, and who comes back. Plausible and Fathom are simple, privacy-focused website analytics tools. PostHog is a product analytics platform that also does web analytics. Google Analytics 4 (GA4) tries to do both, for free.

*Prices checked on 18 October 2026 on plausible.io, usefathom.com/pricing, posthog.com/pricing and Google's Analytics site. US dollars.*

Prices at a glance

Plausible (monthly prices for up to 10,000 monthly pageviews, 30-day free trial):

Plan	Price	Includes
Starter	$9 a month	One site, 3 years of data retention, goals and custom events, GA import
Growth	$14 a month	Up to 3 sites and 3 team members, shared links and embedded dashboards
Business	$19 a month	Up to 10 sites and 10 team members, 5 years of retention, custom properties, Stats API, funnels, ecommerce revenue attribution

Prices rise with traffic. Use the pageview slider on Plausible's pricing section to check your tier. Yearly billing gives two months free.

Fathom (7-day free trial, card required):

Monthly pageviews	Price
Up to 100,000	$15 a month
Up to 200,000	$25 a month
Up to 500,000	$45 a month
Up to 1,000,000	$60 a month

Every Fathom plan includes 50 sites, with extra sites in packs of 50 for $10 a month, and the same features: event and revenue tracking, UTM tracking, shared dashboards, an API and full history while you subscribe. Pageviews and custom events share one allowance across all your sites.

PostHog has a free allowance every month, including 1 million analytics events, 5,000 session recordings, 1 million feature flag requests, 100,000 exceptions and 1,500 survey responses. The free plan is limited to one project with one year of data retention. The pay-as-you-go plan keeps the same free allowance and then charges by usage for each product. PostHog lets you set a billing limit for each product and says it will never charge more than the limit you set.

GA4 is free in its standard version. Google sells a paid enterprise version, Analytics 360.

Data retention

Plausible: 3 years on Starter and Growth, 5 years on Business.
Fathom: full history for as long as you subscribe.
PostHog: one year on the free plan. Longer retention is available on paid plans and add-ons.
GA4: Google's data retention settings let standard properties keep user-level and event data for 2 or 14 months. Longer periods are only available on Analytics 360. Standard aggregated reports aren't affected, but detailed explorations over older data are. If you want to compare this year with last year in detail, set retention to 14 months as soon as you create the property.

Privacy and cookie banners

Plausible says it measures website usage without cookies and without collecting personal data that could identify individual visitors. Fathom says on its pricing page that no cookie banners are required. GA4 uses cookies by default, so in the UK and EU it normally needs consent before it runs, and its data is processed by Google.

PostHog can be configured in different ways. Its product analytics usually identifies signed-in users, which is personal data. Treat it like any other processor of user data in your privacy notice and consent setup.

Whether you need a consent banner depends on everything your site uses, not just analytics. The UK regulator, the ICO, explains the rules in its guidance on cookies and similar technologies.

What each one is good at

Plausible: a single-page dashboard that anyone can read; Google Analytics import; open-source code. Good for blogs, documentation and marketing sites. Its pricing is per site on lower tiers.
Fathom: similar simplicity, with 50 sites on every plan. This makes it good value if you run many small sites with modest total traffic.
PostHog: funnels, retention, user paths, session replay, feature flags, A/B tests and surveys in one tool. It's the one to choose if you need to understand behaviour *inside* your product, and its free allowance is large enough for many early-stage products.
GA4: free, powerful, integrates with Google Ads and Search Console, and can handle very large volumes. The trade-offs are complexity, the consent requirement and short default retention.

Worked examples

A personal blog with 8,000 pageviews a month: Plausible Starter at $9 a month, Fathom at $15 a month, or GA4 and PostHog for free.
Ten small niche sites with 90,000 pageviews a month in total: Fathom's $15 plan covers all ten sites. On Plausible, ten sites needs the Business plan, at $19 a month or more depending on the traffic tier.
A SaaS app with a marketing site: Many teams use one tool for the marketing site (Plausible, Fathom or GA4) and PostHog for the product, using PostHog's free allowance.

Which to choose

Plausible or Fathom if you want simple, privacy-friendly website stats with no cookie banner from analytics. Fathom is better value for many sites. Plausible is open source and has more plan options.
PostHog if you need product analytics, session replay or feature flags.
GA4 if cost is the main concern, or you depend on Google Ads integration. Configure consent and data retention carefully.