PostHog vs Axiom
Open source product analytics — all-in-one dev tool
vs. Observability for logs, traces, events — serverless-first, infinite scale
Pricing tiers
PostHog
Free (generous)
No credit card. Each product has its own free monthly quota. Great for startups + OSS.
Free
Paid (usage-based)
Pay only what you use, after free quotas. Volume discounts at higher tiers. 6 projects, 7-year retention.
$0 base (usage-based)
Self-Hosted (OSS)
MIT-licensed. Run on your own infra via Docker/k8s. Zero vendor lock-in.
$0 base (usage-based)
Enterprise
Custom. SAML SSO, dedicated CSM, custom SLA.
Custom
Axiom
Personal (Free)
No credit card. 500 GB/month ingest, 10 GB-hr compute, 25 GB storage, 30-day retention max.
Free
Axiom Cloud
$25/month minimum platform fee. Volume-based ingest + query credits. Always-free allowances: 1 TB/mo ingest, 100 GB-hr queries, 100 GB storage.
$25/mo
RBAC Add-on
+$50/month for role-based access control.
$50/mo
Audit Logs Add-on
+$50/month for audit logs.
$50/mo
Directory Sync Add-on
+$100/month for SCIM.
$100/mo
SSO Add-on
+$100/month for SAML SSO.
$100/mo
Enterprise
Custom. Dedicated cluster option, private connectivity, SLA.
Custom
Free-tier quotas head-to-head
Comparing free on PostHog vs personal on Axiom.
| Metric | PostHog | Axiom |
|---|---|---|
| data warehouse rows | 1000000 rows/month | — |
| error tracking exceptions | 100000 exceptions/month | — |
| feature flags requests | 1000000 requests/month | — |
| ingest gb month | — | 500 GB/month |
| llm analytics events | 100000 events/month | — |
| logs gb | 50 GB/month | — |
| product analytics events | 1000000 events/month | — |
| projects | 1 projects | — |
| query compute gb hr | — | 10 GB-hr/month |
| retention max days | — | 30 days |
| retention years | 1 year | — |
| session replay recordings | 5000 recordings/month | — |
| storage gb | — | 25 GB |
| surveys responses | 1500 responses/month | — |
| team members | unlimited members | — |
Features
PostHog · 14 features
- A/B Testing — Experiments with significance analysis.
- Data Pipelines — Export events to BigQuery, Snowflake, S3.
- Data Warehouse — Query external sources (Stripe, Hubspot, S3) alongside events with SQL.
- Error Tracking — Sentry-style error tracking in same platform.
- Feature Flags — Rollout flags with targeting, A/B testing, JSON payloads.
- LLM Analytics — Tracing + cost tracking for OpenAI, Anthropic, Gemini, etc.
- Logs — Centralized log ingest with free 50 GB/month.
- Product Analytics — Events, funnels, trends, retention, paths. SQL insights available.
- Revenue Tracking — Integration with Stripe for revenue + churn metrics.
- Self-Hosting — Docker/Helm. Full feature parity with cloud.
- Session Replay — Watch user sessions. Privacy controls, masked inputs, JS errors.
- SQL Query API — Run ClickHouse SQL over your events via API.
- Surveys — In-app surveys + feedback widgets.
- Workflows — Trigger emails/webhooks on events.
Axiom · 15 features
- API Tokens — Scoped tokens for ingest or query.
- APL (query language) — Axiom Processing Language — Kusto-inspired pipes (`|`). Fast + expressive.
- AWS Lambda Extension — Native extension to ship Lambda logs + traces.
- Cloudflare Integration — Workers + Pages log drain. Log pull from any Cloudflare zone.
- Dashboards — Visualizations from APL queries: line/bar/pie/heatmap/table.
- Datasets — Logical partitions of data. Schema-free; fields auto-indexed.
- Elastic Bulk API compat — Elasticsearch Bulk API endpoint — drop-in replacement.
- Field Explorer — Auto-detected field stats, histograms, top-values per dataset.
- Monitors (alerts) — Threshold + anomaly-based alerting on APL queries. Route to Slack/PagerDuty/emai…
- next-axiom — Next.js logger with automatic correlation + Web Vitals capture.
- OpenTelemetry-native — Ingest OTLP/HTTP + gRPC. No proprietary agent.
- Saved Queries — Save + share APL queries as starters.
- Stream (live tail) — Live tail of incoming events with filter bar.
- Traces — OpenTelemetry-native. Distributed tracing across services.
- Vercel Integration — One-click: Vercel logs + Web Vitals → Axiom.
Developer interfaces
| Kind | PostHog | Axiom |
|---|---|---|
| CLI | — | Axiom CLI |
| SDK | posthog-android, posthog-flutter, posthog-go, posthog-ios (Swift), posthog-js, posthog-node, posthog-php, posthog-python, posthog-react-native, posthog-ruby | axiom-go, @axiomhq/js, axiom-py, axiom-rs, next-axiom |
| REST | PostHog REST API | Axiom REST API, Ingest HTTP endpoint |
| MCP | PostHog MCP | Axiom MCP |
| OTHER | Webhooks + Actions | — |
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