Happenstance vs PostHog

PostHog is powerful but requires SDK integration. Happenstance tracks everything with one script tag—no code changes.

At a Glance

Happenstance

  • ✓ One script tag, zero code changes
  • ✓ AI discovers events from your code
  • ✓ Repository-based pricing (€29/mo for 5 repos)
  • ✓ Unlimited events on all plans
  • ✓ Survives UI refactors automatically
  • ✓ Built-in error tracking

PostHog

  • ✓ Open-source option available
  • ✓ Feature flags & A/B testing
  • ✓ Event-based pricing ($0.00031/event)
  • ✓ Session replay
  • ✓ Self-hosted option
  • ✓ Mature product with large community

Feature Comparison

FeatureHappenstancePostHog
Setup Time 60 seconds~30 min
Code Changes Required NoneSDK integration
Auto-Tracking AI-poweredManual setup
Event Pricing Unlimited$0.00031/event
Starting Price€29/moFree tier, then usage-based
Session ReplayComing soon
Feature FlagsRoadmap
Error Tracking Built-inVia integration
Funnel Analytics
Retention Cohorts
Self-Hosted OptionEnterprise Open source
Why Happenstance for Dev Teams

Happenstance is built for teams who want analytics without the integration burden:

One Script Tag
Add one line of HTML, analytics start flowing. No SDK integration, no configuration files, no code changes to your app.
AI-Powered Discovery
Our AI reads your code and discovers trackable events. Your code stays untouched—tracking survives UI refactors automatically.
Predictable Costs
€29/mo for 5 repos, unlimited events. No surprise bills when you go viral. PostHog charges per event—10M events = $2,480/mo.
Choose Happenstance if:

You want to ship analytics today without touching your codebase

You want tracking that survives UI refactors

You want zero surprise bills—€29/mo, unlimited events

You're tired of manually instrumenting every button click

You want errors + analytics in one tool

You're a startup moving fast—one script tag, done

You don't want to modify your codebase for analytics

Choose PostHog if:

✓ You need session replay functionality

✓ You want feature flags and A/B testing built-in

✓ You prefer open-source solutions

✓ You want to self-host your analytics

✓ You have low event volume (free tier friendly)

✓ You need a mature platform with extensive docs

✓ You want full control over your infrastructure

Pricing Comparison

Happenstance

Repository-based, unlimited events

Free: €0/mo
1 repository, unlimited events
Startup: €29/mo
5 repositories, unlimited events
Growth: €99/mo
20 repositories, unlimited events
No event limits. No surprise bills. Ever.
PostHog

Event-based pricing

Free
1M events/mo, then $0.00031/event
Scale
Usage-based, volume discounts
Example Cost
10M events/mo: ~$2,480/mo
Complex pricing. Costs scale with usage.

Ready to try Happenstance?

One script tag. Zero code changes. Unlimited events.

Get Started Free