Knock vs GrowthBook
Notifications-as-a-service: in-app feeds, email, push, SMS, chat via one API
vs. Open-source feature flags + experimentation — Warehouse Native
Pricing tiers
Knock
Developer
Free forever. 10K messages, 500 guide users, 500 AI credits/month.
$0 base (usage-based)
Starter
$250/mo. 50K messages, 2.5K guide users, 2K AI credits. Remove branding.
$250/mo
Enterprise
Custom pricing. White-label, i18n, data warehouse, Datadog, SCIM, SAML, HIPAA/BAA.
Custom
GrowthBook
Open Source (Self-Host)
MIT-licensed. Unlimited everything. Community support.
$0 base (usage-based)
Cloud — Starter (Free)
Up to 3 users. Unlimited flags + experiments. Warehouse Native included.
Free
Cloud — Pro
$40/user/month. Up to 50 users. Advanced stats, visual A/B editor, CUPED, sequential testing, bandits.
$40/mo
Cloud — Enterprise
Custom. Unlimited users, SSO/SAML, approval flows, data pipelines, exportable audit logs.
Custom
Self-Host Enterprise
Open Source + Enterprise license. Visual A/B editor, advanced metrics, SSO/SAML, approvals, training.
Custom
Free-tier quotas head-to-head
Comparing starter on Knock vs oss on GrowthBook.
| Metric | Knock | GrowthBook |
|---|---|---|
| guide users | 2500 users | — |
| guide users overage | $0.05/user USD/user | — |
| messages monthly | 50000 messages/mo | — |
| messages overage | $0.005/message USD/message | — |
Features
Knock · 13 features
- AI Agents — Autonomous notification drafting & workflow generation.
- Batch + Digest — Group notifications into digests on schedule or window.
- Chat — Slack, Microsoft Teams, Discord.
- Email — Send via SendGrid/Postmark/Resend/Mailgun/AWS SES as relays.
- Guides — In-product messaging, announcements, modals, banners.
- i18n / Localization — Translate templates by user locale.
- In-App Feed — Notification inbox with React/Vue/iOS/Android drop-in components.
- Multi-tenancy — Per-tenant branding, preferences, quiet hours.
- Outbound Webhooks — Subscribe to delivery events.
- Preferences — User + tenant preference center with granular controls.
- Push — iOS (APNs), Android (FCM), Expo, Web Push.
- SMS — Twilio, MessageBird, Telnyx, Vonage as providers.
- Workflows — Visual notification orchestration (branch, batch, delay, throttle).
GrowthBook · 15 features
- Approval Flows — Require reviewer approval on flag changes. Enterprise.
- Audit Logs — Full change history. Exportable on Enterprise.
- Dimensions & Slicing — Break down experiment results by user dimensions.
- Edge SDK Support — Cloudflare Workers, Lambda@Edge, Fastly, Akamai EdgeWorkers, Netlify Edge.
- Experiments — A/B/n with CUPED variance reduction + sequential testing.
- Feature Flags — Boolean + string + number + JSON flags with targeting.
- Feature Reviews (PR-style) — Draft → review → approve flag changes.
- Guardrail Metrics — Auto-monitor key metrics during experiments.
- Metric Catalog — Define + reuse metrics across experiments.
- Multi-Armed Bandits — Adaptive traffic allocation. Pro+.
- Safe Rollouts — Guarded gradual rollouts with automatic rollback.
- SSO / SAML — Enterprise SSO for cloud + self-host EE.
- Sticky Bucketing — User stays in variant even after eligibility changes.
- Visual A/B Test Editor — No-code DOM editor for web experiments. Pro+.
- Warehouse Native — Connect your warehouse + run experiments against your events data.
Developer interfaces
| Kind | Knock | GrowthBook |
|---|---|---|
| CLI | Knock CLI | — |
| SDK | knockapi (Python), knockapi (Ruby), knock-elixir, knock-go, knock-java, @knocklabs/node, @knocklabs/react | Edge SDKs (CF Workers / Lambda@Edge / Fastly / Akamai), growthbook-android, growthbook-flutter, growthbook-go, growthbook-java, growthbook-node, growthbook-php, growthbook-python, growthbook-ruby, growthbook-swift, sdk-javascript, sdk-react |
| REST | Knock REST API | GrowthBook REST API |
| MCP | Knock MCP Server | — |
| OTHER | Outbound Webhooks | Webhooks |
Staxly is an independent catalog of developer platforms. Some links to Knock and GrowthBook 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.
Want this comparison in your AI agent's context? Install the free Staxly MCP server.