PostHog
Semrush
| Feature | PostHog | Semrush |
|---|---|---|
| Pricing | Free / from $0/mo | Free / from $139.95/mo |
| Free Plan | ✓ Yes | ✓ Yes |
| Rating | 4.5 / 5 | 4.6 / 5 |
| Best For | developers, startups, product-teams, privacy-conscious-companies | digital-marketers, agencies, enterprise, ppc-managers |
| Founded | 2020 | 2008 |
| Product Analytics | ✓ | ✗ |
| Session Replay | ✓ | ✗ |
| Feature Flags | ✓ | ✗ |
| Experiments | ✓ | ✗ |
| Surveys | ✓ | ✗ |
| Data Warehouse | ✓ | ✗ |
| Self Hosting | ✓ | ✗ |
| Keyword Research | ✗ | ✓ |
| Site Audit | ✗ | ✓ |
| Rank Tracking | ✗ | ✓ |
| Competitor Analysis | ✗ | ✓ |
| Ppc Tools | ✗ | ✓ |
| Content Marketing | ✗ | ✓ |
| Social Media | ✗ | ✓ |
✓ PostHog Pros
- All-in-one analytics replacing multiple tools
- Generous free tier (1M events/month)
- Self-hostable for full data control
- Feature flags and experiments built-in
✗ PostHog Cons
- Can be complex to set up properly
- Self-hosting requires infrastructure maintenance
- Less polished UI than Amplitude
✓ Semrush Pros
- Most comprehensive marketing toolkit
- Excellent PPC and advertising tools
- Content marketing platform included
- Social media management built-in
✗ Semrush Cons
- Very expensive for small businesses
- Interface can feel overwhelming
- Some data less accurate for non-US markets
The Verdict
PostHog is built for developers and startups, with a focus on product-analytics and session-replay. Semrush targets digital marketers and agencies and leads with keyword-research and site-audit.
On pricing, PostHog is the clear winner for budget-conscious users — starting at $0/mo compared to $139.95/mo for Semrush. That $139.95/mo difference adds up quickly for growing teams.
Both offer free plans, so you can test each with your real workflow before committing to a subscription.
This is a genuinely close comparison. If you can, sign up for both free trials (where available) and run a one-week test with your actual team tasks before deciding.