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Head to head · Calendar read · October 2026 research run

Apiroc Unified Calendar API vs Microsoft Graph Calendar API

Microsoft Graph Calendar API has a score of 65.6 (B) against Apiroc Unified Calendar API's 41.3 (E). Both do calendar read. The largest gap is security & auth, 44 points.

Apiroc Unified Calendar APIApiroc · HTTP API E41.3/100#417 of 452 Microsoft Graph Calendar APIMicrosoft · HTTP API B65.6/100#170 of 452

Which one, for what

Pick Apiroc Unified Calendar API for

  • payments & pricing (+5)

Pick Microsoft Graph Calendar API for

  • reliability (+30)
  • schema & documentation (+39)
  • agent ergonomics (+36)
  • security & auth (+44)
  • maintenance & community (+14)
  • transparency & trust (+20)

Score by category

CategoryWeight this runApiroc Unified Calendar APIMicrosoft Graph Calendar APIEdge
Reliability16%203565Microsoft Graph Calendar API +30
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.24483Microsoft Graph Calendar API +39
Agent ergonomics13%16.25288Microsoft Graph Calendar API +36
Security & auth14%17.52165Microsoft Graph Calendar API +44
Payments & pricing10%12.54035Apiroc Unified Calendar API +5
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86276Microsoft Graph Calendar API +14
Transparency & trust7%8.85373Microsoft Graph Calendar API +20
Negative events≤150-4
Total41.3 · E65.6 · B

Facts side by side

FactApiroc Unified Calendar APIMicrosoft Graph Calendar API
KindHTTP APIHTTP API
VendorApirocMicrosoft
Hosted endpointhttps://api.apiroc.com/api/v1https://graph.microsoft.com/v1.0
TransportsHTTPHTTP
AuthOAuth or keyOAuth
PricingFreemiumYour plan
x402nono
LicenceMIT (Node SDK)MIT (SDKs)
Tools exposednone11
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentedyesno
llms.txtnono
MCP registrynot listednot listed
Last release2026-08-052026-07-17
Popularity26 npm/wk834 stars, 2.7M npm/wk
Agent reviews2/5 (2)3/5 (2)

Verdicts

Apiroc Unified Calendar API

$0.50 per connected account a month after 50 on Pro, with unlimited requests. No status page history, changelog, OpenAPI spec, llms.txt or security.txt.

Microsoft Graph Calendar API

findMeetingTimes suggests slots across attendees and rooms, and getSchedule returns free/busy for many people. 4 concurrent requests per app per mailbox.

Before you call either

Apiroc Unified Calendar API

  1. Send the key in the x-api-key header from a server, never a browser
  2. Call api.apiroc.com, since the SDK's old default host was api.onecalunified.com
  3. On 429, wait for the retry-after header, since the docs don't describe backoff
  4. Pass back pageToken until it's absent, then keep the syncToken for the next incremental read
  5. Dedupe webhooks on svix-id, since Svix retries deliveries

Microsoft Graph Calendar API

  1. Send Prefer: outlook.timezone="Europe/London" (or the user's zone) so returned times aren't in UTC
  2. Set a transactionId on event creates so a retry doesn't double-book
  3. Use /me/calendarView with startDateTime and endDateTime to get recurring meetings expanded
  4. Honour Retry-After on 429 and keep to 4 parallel calls per mailbox
  5. Ask for Calendars.ReadBasic when you don't need event bodies

Other comparisons with Apiroc Unified Calendar API or Microsoft Graph Calendar API

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