fourzerotwo-si Holidays API
World Public Holidays: Public holidays for ~40 countries and their regions, is-it-a-holiday checks and business-day maths.
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OpenAPI Specification
openapi: 3.2.0
info:
title: Fourzerotwo Si Holidays API
version: 1.1.0
contact:
url: https://fourzerotwo.si
description: 'Operations tagged holidays across 2 of this provider''s published API definitions: openapi.json, fourzerotwo-si-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://fourzerotwo.si
tags:
- name: holidays
description: 'World Public Holidays: Public holidays for ~40 countries and their regions, is-it-a-holiday checks and business-day maths.'
paths:
/v1/holidays/year:
get:
operationId: holidays__year
summary: 'World Public Holidays: Holidays in a year'
description: 'Official public holidays for a country (or region provider, e.g. Germany/Bavaria) in a year. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- holidays
externalDocs:
url: https://fourzerotwo.si/apis/holidays/year
parameters:
- name: country
in: query
required: true
description: ISO code (US, DE, FR, JP…) or provider name
schema:
type: string
example: DE
- name: year
in: query
required: false
description: Year (default this year)
schema:
type: integer
example: 2026
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.001000'
x-free-tier: free
x-mcp-tool: holidays__year
servers:
- url: https://fourzerotwo.si
/v1/holidays/check:
get:
operationId: holidays__check
summary: 'World Public Holidays: Holiday & business-day check'
description: 'Is a date a public holiday or business day in a country; add N business days; next business day. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- holidays
externalDocs:
url: https://fourzerotwo.si/apis/holidays/check
parameters:
- name: country
in: query
required: true
description: ISO code
schema:
type: string
example: US
- name: date
in: query
required: true
description: YYYY-MM-DD
schema:
type: string
example: '2026-11-26'
- name: add
in: query
required: false
description: Business days to add
schema:
type: integer
example: 3
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.001000'
x-free-tier: free
x-mcp-tool: holidays__check
servers:
- url: https://fourzerotwo.si
/v1/holidays/countries:
get:
operationId: holidays__countries
summary: 'World Public Holidays: Supported countries'
description: 'Every country and regional provider supported. Price: $0.0005 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- holidays
externalDocs:
url: https://fourzerotwo.si/apis/holidays/countries
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.000500'
x-free-tier: free
x-mcp-tool: holidays__countries
servers:
- url: https://fourzerotwo.si
components:
responses:
PaymentRequired:
description: x402 payment required. The body (also base64 in the PAYMENT-REQUIRED header) lists accepted payments.
headers:
PAYMENT-REQUIRED:
schema:
type: string
description: Base64 JSON x402 v2 PaymentRequired
content:
application/json:
schema:
type: object
properties:
x402Version:
type: integer
error:
type: string
accepts:
type: array
items:
type: object
Error:
description: 400 = invalid input, 404 = not found at the source, 502 = the source failed. Never charged.
content:
application/json:
schema:
type: object
properties:
error:
type: string
charged:
type: boolean
securitySchemes:
freeKey:
type: apiKey
in: header
name: X-API-Key
description: Optional free key (fzt_…) for the free tier.
x-refined-from:
- openapi.json
- fourzerotwo-si-openapi.json