# Japan JGB Yield Curve

> Japan JGB Yield Curve is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-29).

Returns Japan Government Bond (JGB) yield curve data across maturities (1Y–40Y) for up to 31 days of history, sourced from Japan's Ministry of Finance.

## Facts

- Endpoint: POST https://api.vextorium.com/v1/japan-jgb-yield-curve?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/japan-jgb-yield-curve-c3f762a6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_80JhqkA2XvkMVOJ_vN-h4

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 japan-jgb-yield-curve-c3f762a6 -d '<json body>'
```

Example prompt: What does the Japan government bond yield curve look like right now? Give me yields across all maturities from 1Y to 40Y for the last 10 days, including the 10Y-2Y spread.

## When to prefer this

Choose this endpoint when you need official, Ministry of Finance Japan JGB yield curve data across the full maturity spectrum (1Y–40Y) with historical series. Prefer over general financial data APIs when you specifically need Japanese sovereign bond rates with authoritative sourcing and the 10Y-2Y spread pre-calculated.

## Known failure modes

- days parameter out of range (>31 or <1) may return validation error
- Ministry of Finance data may be unavailable on Japanese public holidays or weekends causing stale or missing dates
- Network or payment failure returns HTTP 402 if USDC payment not processed
- Empty series if requested days fall entirely on non-trading days

## How this service works

244 pay-per-call data APIs for AI agents: official statistics and economy (ECB, Fed, Eurostat, World Bank, SEC, BOE, INE), crypto prices and sentiment, Spanish public data, compliance (sanctions, VAT, IBAN, LEI), science, weather, web and developer tools and local AI text tools. Pay in USDC via x402.

## Output

Returns a JSON object with the latest JGB yield curve snapshot (yields_pct for maturities 1Y, 2Y, 3Y, 4Y, 5Y, 6Y, 7Y, 8Y, 9Y, 10Y, 15Y, 20Y, 25Y, 30Y, 40Y in percent), a time-series array of daily yield curves for the requested history window, the 10Y-2Y spread, country metadata, and source attribution to Japan's Ministry of Finance.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "days": {
   "type": "integer",
   "description": "Days of history, 1-31 (default 10)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "date": "2026-10-19",
  "series": [
   {
    "date": "2026-10-15",
    "yields_pct": {
     "1Y": 1.652,
     "2Y": 1.913,
     "3Y": 2.045,
     "4Y": 2.209,
     "5Y": 2.331,
     "6Y": 2.431,
     "7Y": 2.535,
     "8Y": 2.686,
     "9Y": 2.818,
     "10Y": 2.948,
     "15Y": 3.489,
     "20Y": 3.786,
     "25Y": 4.048,
     "30Y": 4.024,
     "40Y": 4.031
    }
   },
   {
    "date": "2026-10-16",
    "yields_pct": {
     "1Y": 1.649,
     "2Y": 1.918,
     "3Y": 2.05,
     "4Y": 2.214,
     "5Y": 2.335,
     "6Y": 2.436,
     "7Y": 2.546,
     "8Y": 2.695,
     "9Y": 2.827,
     "10Y": 2.958,
     "15Y": 3.502,
     "20Y": 3.803,
     "25Y": 4.066,
     "30Y": 4.04,
     "40Y": 4.038
    }
   }
  ],
  "source": "Source: Ministry of Finance Japan, Interest Rate (JGB), https://www.mof.go.jp/english/policy/jgbs/reference/interest_rate/ (Public Data License 1.0). Processed by Vextorium.",
  "country": "Japan",
  "yields_pct": {
   "1Y": 1.642,
   "2Y": 1.904,
   "3Y": 2.034,
   "4Y": 2.192,
   "5Y": 2.313,
   "6Y": 2.416,
   "7Y": 2.52,
   "8Y": 2.67,
   "9Y": 2.803,
   "10Y": 2.935,
   "15Y": 3.477,
   "20Y": 3.776,
   "25Y": 4.055,
   "30Y": 4.028,
   "40Y": 4.04
  },
  "spread_10y_2y_pct": 1.031
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/japan-jgb-yield-curve-c3f762a6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)