Website Analytics Stack for Startups
Most startups need three layers: a tag manager to install tracking, web analytics for traffic and campaigns, and product analytics for what users do after sign-up. Add the CRM to connect it all to revenue. Start small and add tools when a question needs them.
What analytics tools does a startup need?
Google Tag Manager to install and manage tags, GA4 for traffic sources and marketing conversions, and a product analytics tool such as PostHog for activation and retention. Tie them together with one event tracking plan so the same action has the same name everywhere.
| Layer | Tools | Answers |
|---|---|---|
| Tag manager | Google Tag Manager | How tracking gets onto the site, without a deploy for every change |
| Web analytics | GA4, or privacy-first tools such as Plausible or Fathom | Where visitors come from and which campaigns convert |
| Product analytics | PostHog, Mixpanel, Amplitude | What users do in the product: activation, retention, features |
| Revenue | Your CRM and billing | Which sources become customers and revenue |
GA4 or PostHog?
Usually both, for different jobs. GA4 is free, connects to Google Ads and is the standard for marketing reporting. PostHog is built for product questions: funnels inside the app, session replay, feature flags and experiments. See GA4 setup for SaaS and PostHog product analytics.
What about privacy-first analytics?
Tools such as Plausible and Fathom count visits without cookies and give a simple dashboard. They suit content sites and teams that want minimal consent friction. They don’t replace GA4 if you run Google Ads, which needs conversion data. Consent rules are in consent and privacy.
In what order should you add tools?
- Install Google Tag Manager on every page.
- Add GA4 through GTM with a handful of key events.
- Set UTM rules before the first campaign; see UTM tracking.
- Add product analytics when you have users to activate.
- Connect the CRM to measure revenue by source.
The wider marketing tool set is covered in the SaaS marketing stack.
Questions first, tools second.
Analytics is only useful when it answers a decision you need to make. Start from the decision.
What should you avoid?
- Installing every tool before you know the questions.
- Hard-coding tags in the site so marketing needs a developer for each change.
- Different event names in different tools.
- Dashboards no one reads; see dashboards and reporting.
Frequently asked questions
What analytics tools does a startup need?
A tag manager (Google Tag Manager), web analytics (GA4) and, once you have users, product analytics such as PostHog.
Should I use GA4 or PostHog?
Usually both: GA4 for marketing and traffic, PostHog for in-product behaviour.
Is Google Analytics free?
GA4 is free for standard properties. Google Analytics 360 is the paid enterprise version.
What is a privacy-first analytics tool?
Tools such as Plausible and Fathom that count visits without cookies and collect less personal data.
Do I need Google Tag Manager?
It isn’t required, but it lets you add and change tracking without code deploys.
When should I add product analytics?
When you have users signing up and need to understand activation and retention.