Staxly

Knock vs Cal.com

Notifications-as-a-service: in-app feeds, email, push, SMS, chat via one API
vs. Open-source scheduling infrastructure — the self-hostable Calendly alternative

Knock websiteCal.com website

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
Knock website

Cal.com

Free (Cloud)
$0. 1 user. Unlimited event types. Unlimited meetings. Cal branding.
Free
Self-Hosted (OSS)
Free forever. AGPL-3.0. Docker/K8s deploy. Full feature parity with cloud.
$0 base (usage-based)
Teams
$12/user/mo. Round-robin, collective events, routing forms, Cal Video, Workflows.
$12/mo
Organizations
$37/user/mo. SSO, advanced routing, dashboards, analytics, dedicated support.
$37/mo
Enterprise
Custom. SAML, HIPAA, dedicated deployments, security reviews.
Custom
Cal.com website

Free-tier quotas head-to-head

Comparing starter on Knock vs free on Cal.com.

MetricKnockCal.com
guide users2500 users
guide users overage$0.05/user USD/user
messages monthly50000 messages/mo
messages overage$0.005/message USD/message

Features

Knock · 13 features

  • AI AgentsAutonomous notification drafting & workflow generation.
  • Batch + DigestGroup notifications into digests on schedule or window.
  • ChatSlack, Microsoft Teams, Discord.
  • EmailSend via SendGrid/Postmark/Resend/Mailgun/AWS SES as relays.
  • GuidesIn-product messaging, announcements, modals, banners.
  • i18n / LocalizationTranslate templates by user locale.
  • In-App FeedNotification inbox with React/Vue/iOS/Android drop-in components.
  • Multi-tenancyPer-tenant branding, preferences, quiet hours.
  • Outbound WebhooksSubscribe to delivery events.
  • PreferencesUser + tenant preference center with granular controls.
  • PushiOS (APNs), Android (FCM), Expo, Web Push.
  • SMSTwilio, MessageBird, Telnyx, Vonage as providers.
  • WorkflowsVisual notification orchestration (branch, batch, delay, throttle).

Cal.com · 16 features

  • AvailabilityMultiple schedules per user.
  • Buffer TimePadding between meetings.
  • Cal VideoBuilt-in video conferencing.
  • EmbedInline/popup/floating-button embeds.
  • Event TypesOne-on-one, group, collective, round-robin.
  • Insights DashboardBooking trends + team analytics.
  • Paid BookingsStripe integration for paid appointments.
  • Platform APIEmbed scheduling in your SaaS.
  • Recurring EventsWeekly/monthly recurring bookings.
  • Round-RobinDistribute bookings across team.
  • Routing FormsRoute leads by answers.
  • Self-HostDeploy to your infra.
  • SSOSAML + OIDC.
  • Timezone DetectionAuto-detect viewer timezone.
  • WebhooksOutbound events.
  • WorkflowsAutomated email/SMS reminders.

Developer interfaces

KindKnockCal.com
CLIKnock CLIcal CLI (self-host)
SDKknockapi (Python), knockapi (Ruby), knock-elixir, knock-go, knock-java, @knocklabs/node, @knocklabs/react@calcom/embed-react
RESTKnock REST APICal.com REST API v2, Platform API (embed in SaaS)
MCPKnock MCP Server
OTHEROutbound WebhooksCal.com Dashboard, Cal.com Webhooks
Staxly is an independent catalog of developer platforms. Some links to Knock and Cal.com 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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