# Mart402 Japan Business Days & Statutory Deadlines

> Mart402 Japan Business Days & Statutory Deadlines is a paid API for AI agents from mart402.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-01).

Calculates Japanese business days, public holidays (including equinox and substitute holidays), business-day arithmetic, tax filing deadlines with holiday shifts, and wareki (Japanese era) conversions for dates between 1980 and 2099.

## Facts

- Endpoint: POST https://mart402.com/v1/jp-business-days?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mart402-japan-business-days-statutory-deadlines-c5406168
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kOpONHYZs2np7zSBGDLbF

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 mart402-japan-business-days-statutory-deadlines-c5406168 -d '<json body>'
```

Example prompt: Is March 21, 2025 a Japanese business day, and if not, what is the next business day? Also tell me what the tax filing deadline would be if it's originally due on that date.

## When to prefer this

Choose this endpoint when you need authoritative Japanese business calendar logic — especially equinox holidays (whose dates vary by year), substitute holidays, statutory tax deadline shifts, or wareki conversions — rather than relying on a generic calendar library that may not have current Japanese holiday rules or era names. Covers 1980–2099 with statutory accuracy.

## Known failure modes

- Date outside 1980–2099 range returns an error or out-of-range response
- Invalid date format (non-ISO string) causes a validation error
- Unsupported 'kind' or 'mode' enum value returns a bad-request error
- Missing required fields (e.g. base_date) return a 400-class error
- Network or payment authorization failure (x402 protocol) prevents call execution

## How this service works

Japan business days + statutory deadlines: holidays (equinox + substitute), business-day arithmetic, tax filing deadlines with holiday shift, wareki conversion. 1980-2099. $0.003/call.

## Output

Returns whether a date is a Japanese business day or holiday (including equinox and substitute holidays), the result of business-day arithmetic (e.g. next/previous business day, N-day offset), tax filing deadlines adjusted for holiday shifts, and wareki-format date representations. Coverage spans 1980–2099.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "kind": {
   "type": "string"
  },
  "mode": {
   "type": "string"
  },
  "base_date": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mart402-japan-business-days-statutory-deadlines-c5406168/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mart402.com](https://www.zero.xyz/host/mart402.com/llms.txt)