Overview
IsDayOff.ru is a minimalist REST API that returns whether a given date is a working day, non-working day, or short (pre-holiday) day for Russia and several CIS countries, as well as the United States. The response is a single character (0, 1, or 4), making it trivially easy to parse in any language. No authentication is required.
Beginner Tip
This is one of the most beginner-friendly APIs available: no key, no JSON parsing — just a GET request that returns a single digit. Try it in your browser by visiting https://isdayoff.ru/20250101 to see the result immediately.
Available Data
The kind of data this API exposes, based on its documentation. We could not call the endpoint to confirm the exact field names.
Example Response
Illustrative shape only — we were not able to call this endpoint (it requires credentials or exposes no public sample URL), so the fields below show the kind of data this API returns rather than a recorded response.
{
"input": "[email protected]",
"is_valid": true,
"format_valid": true,
"details": "Input passes all validation checks"
} Field Reference
(response body) Single character: 0 means working day, 1 means non-working day, 4 means short pre-holiday day, 100 means an error occurred Implementation Example
Calls a real endpoint of this API. Replace any placeholder credentials with your own key.
const url = "https://isdayoff.ru/";
const response = await fetch(url);
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data); What Can You Build?
Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.
Common Errors & Troubleshooting
Generated guidance based on this API's documentation, not observed by us. Treat it as a starting point and check against the provider's own error reference.
Metadata Score Breakdown
Estimated from metadata — endpoint not independently tested
Metadata estimate · endpoint not independently tested
Technical Specifications
Related Tags
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