# QuantOracle FX Purchasing Power Parity Calculator

> QuantOracle FX Purchasing Power Parity Calculator is a paid API for AI agents from api.quantoracle.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Calculates the PPP-adjusted exchange rate and overvaluation/undervaluation percentage given a base spot rate and inflation differentials over a time horizon

## Facts

- Endpoint: POST https://api.quantoracle.dev/v1/fx/purchasing-power-parity
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-quantoracle-dev-bddf84be
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_fw0KEtHZUG-l02qUyW7uy

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 api-quantoracle-dev-bddf84be -d '<json body>'
```

Example prompt: What's the PPP-adjusted exchange rate for EUR/USD if the current spot rate is 1.08, eurozone inflation is 2.1% and US inflation is 3.2%, projected over 3 years — and is the euro overvalued or undervalued relative to that fair value?

## When to prefer this

Use this endpoint when you need a fast, quantitative PPP calculation with explicit inflation rate inputs and a defined time horizon — ideal for FX analysis pipelines, currency fair-value models, or macro research automation where you already have spot rates and inflation estimates and need the derived PPP rate and misalignment metrics in real time.

## Known failure modes

- Missing required fields (base_spot_rate, foreign_inflation, domestic_inflation, time_years) returns a 400 validation error
- Negative time horizon or zero spot rate may return a 422 unprocessable entity error
- Payment failure or insufficient USDC balance returns a 402 payment required error
- Invalid inflation values (e.g. extremely large numbers) may return computation errors

## How this service works

QuantOracle: fx/purchasing-power-parity

## Output

Returns the PPP-implied exchange rate, the overvaluation or undervaluation percentage relative to the current spot rate, the real exchange rate, and the compounded inflation differential — all computed in about 10ms.

## Example request

```json
{
 "input": {
  "body": {
   "time_years": 1,
   "base_spot_rate": 1.25,
   "foreign_inflation": 0.02,
   "domestic_inflation": 0.03
  },
  "type": "http",
  "method": "POST",
  "bodyType": "json"
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "time_years": {
   "type": "number",
   "title": "Time Years",
   "default": 1,
   "description": "Time horizon in years"
  },
  "base_spot_rate": {
   "type": "number",
   "title": "Base Spot Rate",
   "description": "Current spot exchange rate"
  },
  "foreign_inflation": {
   "type": "number",
   "title": "Foreign Inflation",
   "description": "Foreign inflation rate"
  },
  "domestic_inflation": {
   "type": "number",
   "title": "Domestic Inflation",
   "description": "Domestic inflation rate"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-quantoracle-dev-bddf84be/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.quantoracle.dev](https://www.zero.xyz/host/api.quantoracle.dev/llms.txt)