# Business Day & Deadline API – Add/Subtract Business Days

> Business Day & Deadline API – Add/Subtract Business Days is a paid API for AI agents from businessdayapi.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-11).

Calculates a future or past business date by adding or subtracting a specified number of business days from a start date, accounting for public holidays and weekend rules across ~200 countries and their subdivisions.

## Facts

- Endpoint: GET https://businessdayapi.com/v1/add?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/business-day-deadline-api-add-subtract-business-days-a3bdfa43
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VuGjjpnboNFpdilPu0aIZ

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability business-day-deadline-api-add-subtract-business-days-a3bdfa43
```

Example prompt: What date is 10 business days after April 1, 2026 in Germany — specifically Bavaria — and which holidays or weekends does it skip?

## When to prefer this

Choose this endpoint when you need verified, up-to-date business-day arithmetic across international jurisdictions, especially when subdivision-level accuracy (e.g. German Bundesländer, US states) or non-standard weekend rules (e.g. Friday–Saturday in Egypt) matter. It is preferable over generic date-math libraries that lack maintained holiday databases, or over building custom holiday calendars. It is informational and should not replace legal counsel for binding deadlines.

## Known failure modes

- Missing required query parameters (start, days, country) returns a 400 error
- Invalid or unsupported ISO country code returns an error or empty holiday data
- Unsupported subdivision code may silently fall back to country-level holidays
- Negative days value (subtraction) may not be supported by all country calendars
- Holiday data may lag for newly announced public holidays; verifiedAt timestamp indicates data freshness
- Payment failure via x402 returns 402 Payment Required before computation is attempted

## How this service works

Verified, always-current business-day arithmetic for ~200 countries incl. subdivisions (German Bundeslaender, US states) and correct per-country weekend rules (e.g. Fri/Sat in Egypt). Informational only — verify legally binding deadlines with the competent authority. Not legal advice.

## Output

A JSON object containing the computed result date (YYYY-MM-DD), the original start date and days-requested, the country code used, a list of skipped dates with their reason (holiday or weekend) and holiday name where applicable, the data source (nager.date), and a verifiedAt timestamp indicating when the holiday data was last confirmed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "start",
      "days",
      "country"
     ],
     "properties": {
      "days": {
       "type": "integer",
       "description": "business days to add (negative = subtract)"
      },
      "start": {
       "type": "string",
       "description": "ISO start date YYYY-MM-DD"
      },
      "region": {
       "type": "string",
       "description": "optional ISO 3166-2 subdivision suffix, e.g. BY (Bavaria), CA (California)"
      },
      "country": {
       "type": "string",
       "description": "ISO 3166-1 alpha-2 country code, e.g. DE, US, JP"
      },
      "weekend": {
       "type": "string",
       "description": "optional override: sat-sun | fri-sat | custom:THU,FRI"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "days": 3,
  "start": "2026-04-01",
  "source": "nager.date",
  "country": "DE",
  "skipped": [
   {
    "date": "2026-04-03",
    "reason": "holiday",
    "holidayName": "Karfreitag"
   }
  ],
  "resultDate": "2026-04-08",
  "verifiedAt": "2026-08-17T00:00:00Z"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/business-day-deadline-api-add-subtract-business-days-a3bdfa43/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from businessdayapi.com](https://www.zero.xyz/host/businessdayapi.com/llms.txt)