API archive entry · source-reported
TimeZones iCal Library
Database of official time zones and corresponding iCal VTIMEZONE blocks
Other Calendar APIs
These records share a directory category and are ordered by similarity of reported access facts. They are a shortlist, not proof of drop-in compatibility.
Byabbe
Seach histories from wikipedia for a particular day
No auth · HTTPS reported · CORS Unknown
Non-Working Days
Database of ICS files for non working days
No auth · HTTPS reported · CORS Unknown
UK Bank Holidays
Bank holidays in England and Wales, Scotland and Northern Ireland
No auth · HTTPS reported · CORS Unknown
Mother's Day Calendar
Mother's Day dates, country rules, sources and confidence as static JSON and CSV
No auth · HTTPS reported · CORS Yes
CountdownsHQ
Dates and timezone-correct countdowns for 150+ holidays and observances in 18 countries
No auth · HTTPS reported · CORS Yes
Intellibook
Appointment booking and availability API for salons and clinics
No auth · HTTPS reported · CORS Yes
How to compare them
Coverage
Compare exact endpoints, fields, geography, history, and update frequency.
Operating cost
Model request volume, caching, overages, support, and migration cost.
Integration risk
Test auth, errors, pagination, latency, versioning, and outage behavior.
Data rights
Review attribution, redistribution, retention, privacy, and commercial-use terms.
Source reference
This page separates source-reported facts from questions that need live provider verification.