Staxly

MongoDB Atlas vs Cal.com

Managed MongoDB with search, vector, stream processing
vs. Open-source scheduling infrastructure — the self-hostable Calendly alternative

MongoDB AtlasCal.com website

Pricing tiers

MongoDB Atlas

M0 — Free
Shared cluster, 512 MB storage, 100 ops/sec, 32 MB sort memory. Learning/exploration.
Free
Flex — Serverless
Autoscales 0-500 ops/sec. 5 GB storage. Pay-as-you-go, up to ~$30/mo.
$8/mo
M2 — Shared
Shared, 2 GB storage. Staging / small apps.
$9/mo
M5 — Shared
Shared, 5 GB storage.
$25/mo
M10 — Dedicated
2 GB RAM, 2 vCPU, 10-128 GB storage. First dedicated tier.
$57/mo
M20 — Dedicated
4 GB RAM, 2 vCPU, 20-256 GB storage.
$144/mo
M30 — Dedicated
8 GB RAM, 2 vCPU, 40-512 GB storage.
$389/mo
M40 — Dedicated
16 GB RAM, 4 vCPU, 80 GB-1 TB storage.
$749/mo
M50 — Dedicated
32 GB RAM, 8 vCPU, 160 GB-4 TB storage.
$1440/mo
M60 — Dedicated
64 GB RAM, 16 vCPU.
$2844/mo
M80 — Dedicated
128 GB RAM, 32 vCPU, 750 GB-4 TB.
$5256/mo
M300 — Dedicated
384 GB RAM, 96 vCPU.
$15732/mo
Enterprise
Multi-region Advanced, private network, BYOK, dedicated support.
Custom
MongoDB Atlas

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 m0 on MongoDB Atlas vs free on Cal.com.

MetricMongoDB AtlasCal.com
backups0 backups
ops per sec100 ops/sec
sort memory mb32 MB
storage gb0.5 GB

Features

MongoDB Atlas · 14 features

  • Atlas App ServicesBackend-as-a-service: Functions, HTTPS endpoints, users + auth, sync.
  • Atlas ChartsEmbedded dashboards + visualizations from Atlas data.
  • Atlas DatabaseCore MongoDB with automated backups, monitoring, scaling on AWS/Azure/GCP.
  • Atlas Data FederationQuery across Atlas, S3, and HTTP endpoints in one pipeline.
  • Atlas Device Sync (Realm)Offline-first mobile DB that syncs bidirectionally with Atlas.
  • Atlas SearchApache Lucene-based full-text search integrated into MongoDB aggregation pipelin
  • Atlas Stream ProcessingContinuous processing of MongoDB change streams + Kafka. Pipeline aggregations o
  • Atlas TriggersDatabase change triggers, scheduled triggers. Run Atlas Functions (Node.js).
  • Atlas Vector SearchVector similarity search via $vectorSearch operator. HNSW index. Up to 4096 dims
  • BYOK EncryptionBring your own KMS key (AWS KMS, Azure Key Vault, GCP KMS).
  • Data APIRead/write via REST. Alternative to drivers for edge/serverless.
  • Multi-Region ClustersSingle cluster distributed across multiple regions for HA + low latency.
  • Online ArchiveTiered storage: automatic cold data movement to cheaper S3-backed storage.
  • Private NetworkingVPC Peering, PrivateLink, CIDR allowlist.

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

KindMongoDB AtlasCal.com
CLIAtlas CLI, MongoDB Shell (mongosh)cal CLI (self-host)
SDKAtlas Device SDK (Realm), MongoDB Go Driver, MongoDB Java Driver, MongoDB .NET/C# Driver, mongodb (Node driver), mongodb (Rust), pymongo@calcom/embed-react
RESTAtlas Admin API, Atlas Data APICal.com REST API v2, Platform API (embed in SaaS)
MCPMongoDB MCP Server
OTHERMongoDB Compass (GUI), MongoDB Wire ProtocolCal.com Dashboard, Cal.com Webhooks
Staxly is an independent catalog of developer platforms. Some links to MongoDB Atlas 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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