PostHog vs Fastly
Open source product analytics — all-in-one dev tool
vs. Edge cloud platform — CDN + compute + security + observability
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
Fastly
Free Trial
Free allowances: 100 GB bandwidth, 1M CDN requests, 10M Edge Compute requests, 100M vCPU-ms, 500K DDoS requests.
Free
Pay-as-you-go
Usage-based rates with volume discounts. No minimum commitment.
$0 base (usage-based)
Basic Package
$1,500/month. 100M requests. Standard support.
$1500/mo
Starter Package
$6,000/month. 500M requests. Gold support.
$6000/mo
Advantage
Custom. 2B requests. Gold support.
Custom
Ultimate
Custom. 5B+ requests. Enterprise support.
Custom
Free-tier quotas head-to-head
Comparing free on PostHog vs free on Fastly.
| Metric | PostHog | Fastly |
|---|---|---|
| data warehouse rows | 1000000 rows/month | — |
| error tracking exceptions | 100000 exceptions/month | — |
| feature flags requests | 1000000 requests/month | — |
| llm analytics events | 100000 events/month | — |
| logs gb | 50 GB/month | — |
| product analytics events | 1000000 events/month | — |
| projects | 1 projects | — |
| retention years | 1 year | — |
| session replay recordings | 5000 recordings/month | — |
| 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.
Fastly · 16 features
- API Security — Schema validation + rate limiting.
- Bot Management — Behavioral bot detection + mitigation.
- CDN — Global Varnish-based CDN with VCL customization.
- Compute@Edge — Wasm-based serverless at 200+ POPs. Rust, JS, Go.
- DDoS Protection — Included on all plans.
- Fanout (WebSockets) — Persistent connection fan-out at edge.
- Image Optimization — On-the-fly resize/format/quality.
- Instant Purge — <150ms global cache invalidation.
- KV Store (Config) — Edge key-value store for config.
- Live Streaming — HLS + DASH live video delivery.
- Log Streaming — Real-time logs to S3, Datadog, Splunk, Azure, GCS, Kafka.
- Managed TLS — Automated cert issuance + renewal.
- Next-Gen WAF — Signal Sciences acquired — runtime app protection.
- Real-Time Analytics — Sub-second log streaming + metrics.
- Secret Store — Encrypted secrets at edge.
- Shield POP — Origin shield to reduce origin load.
Developer interfaces
| Kind | PostHog | Fastly |
|---|---|---|
| CLI | — | Fastly CLI |
| SDK | posthog-android, posthog-flutter, posthog-go, posthog-ios (Swift), posthog-js, posthog-node, posthog-php, posthog-python, posthog-react-native, posthog-ruby | compute-go-starter, compute-js-starter, compute-rust-starter |
| REST | PostHog REST API | Fastly API |
| MCP | PostHog MCP | — |
| OTHER | Webhooks + Actions | Compute@Edge (Wasm), VCL (Varnish) |
Staxly is an independent catalog of developer platforms. Some links to PostHog and Fastly may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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