# Checkiday - National Holiday and Event API

**Canonical:** https://apis.io/providers/checkiday-national-holiday-api/  
**Website:** https://apilayer.com/marketplace/checkiday-api  
**APIs profiled:** 1

Industry-leading Holiday and Event API by Checkiday, providing data on more than 5,000 national, international, and bizarre holidays and observances with thousands of descriptions, hashtags, images, founders, alternate names, and multi-year occurrence patterns. Routed through the apilayer marketplace with X-API-Key (apikey) header authentication and official client libraries for JavaScript, TypeScript, Python, C#, PHP, Go, Dart, Rust, and Java/Kotlin. Trusted since 2011 by media organizations including CNN, The New York Times, and USA Today.

## Kin Score — 51.1 / 100 (developing)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 51.1).

| Facet | Score |
|---|---|
| Discoverability | 75.9 |
| Contract Quality | 72.0 |
| Governance | 9.8 |
| Contract Governance | 9.8 |
| Operational Transparency | 57.9 |
| Developer Ergonomics | 27.4 |
| Commercial Clarity | 56.6 |
| Access Clarity | 56.6 |

## Agent readiness — 38.3 (agent-ready)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | na |
| MCP Server | no |
| Auth Clarity | yes |
| Idempotency | na |
| Error Semantics | no |
| OpenAPI Examples | no |
| Rate Limit Signal | verified |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | na |

## Access

Freemium · Self-serve signup — onboarding: self-serve, pricing: freemium, trial: no (confidence: high).

## APIs (1)

- **Checkiday - National Holiday and Event API Events API** — List, search, and retrieve holidays, observances, and events.

## Agentic access (1)

- **Checkiday National Holiday Api Agentic Access** — 3 operations

## Security (2)

- **Checkiday National Holiday Api Authentication** — apiKey · 1 scheme
- **Checkiday National Holiday Api Domain Security** — TLSv1.3 · HSTS · DMARC

## Plans (1)

- **Checkiday Plans Pricing**

## Tags

Calendar, Holidays, Event, Observances, Dates, Time, Public APIs

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/checkiday-national-holiday-api/). Scores are computed from the provider's own public artifacts under a published rubric.