# Currency Strength API
> A live currency strength meter as an API — it ranks 30+ major currencies by how much each has strengthened or weakened against the whole basket over a chosen period, computed from European Central Bank reference rates. Pull the full strength ranking, one currency's strength with its rank and per-pair changes, or any pair's cross-rate and period change. The classic dashboard forex traders watch, delivered as clean JSON. Distinct from raw exchange-rate and conversion APIs — this is the derived strength analytic.

## Authentication
All requests require your oanor API key in the `x-oanor-key` header. Get one at https://www.oanor.com/developer/keys.

```bash
curl -H "x-oanor-key: oanor_live_…" "https://api.oanor.com/currencystrength-api/..."
```

## Pricing
- **Free** (Free) — 300 calls/Mo, 3 req/s
- **Trader** ($10/Mo) — 12,000 calls/Mo, 10 req/s
- **Pro** ($27/Mo) — 60,000 calls/Mo, 25 req/s
- **Business** ($62/Mo) — 300,000 calls/Mo, 45 req/s

## Endpoints

### Strength

#### `GET /v1/currency` — One currency strength + per-pair changes

**Parameters:**
- `code` (query, required, string) — 3-letter currency code Example: `USD`
- `period` (query, optional, string) — 1d | 7d | 2w | 1m | 3m Example: `1m`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/currencystrength-api/v1/currency?code=USD&period=1m"
```

**Response:**
```json
{
    "data": {
        "of": 30,
        "name": "United States Dollar",
        "rank": 2,
        "period": "1m",
        "to_date": "2026-06-08",
        "currency": "USD",
        "strength": 2.001,
        "from_date": "2026-05-08",
        "vs_currencies": [
            {
                "currency": "CNY",
                "change_pct": -0.284,
                "cross_rate": 6.781889
            },
            {
                "currency": "HKD",
                "change_pct": 0.1,
                "cross_rate": 7.835962
            },
            {
                "currency": "ZAR",
                "change_pct": 0.27,
                "cross_rate": 16.463692
            },
            {
                "currency": "ILS",
                "change_pct": 0.403,
                "cross_rate": 2.916811
            },
            {
                "currency": "MXN",
                "change_pct": 1.025,
                "cross_rate": 17.412912
            },
            {
                "currency": "INR",
                "change_pct": 1.291,
                "cross_rate": 95.708406
            },
            {
                "currency": "SGD",
                "change_pct": 1.532,
                "cross_rate": 1.287262
            },
            {
                "currency": "CZK",
                "change_pct": 1.609,
                "cross_rate": 20.9974
            },
            {
                "currency": "TRY",
                "change_pct": 1.62,
                "cross_rate":
…(truncated, see openapi.json for full schema)
```

#### `GET /v1/pair` — Cross-rate and period change for a pair

**Parameters:**
- `base` (query, required, string) — Base currency Example: `EUR`
- `quote` (query, required, string) — Quote currency Example: `USD`
- `period` (query, optional, string) — 1d | 7d | 2w | 1m | 3m Example: `7d`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/currencystrength-api/v1/pair?base=EUR&quote=USD&period=7d"
```

**Response:**
```json
{
    "data": {
        "base": "EUR",
        "pair": "EURUSD",
        "rate": 1.154,
        "quote": "USD",
        "period": "7d",
        "to_date": "2026-06-08",
        "from_date": "2026-06-01",
        "rate_then": 1.1646,
        "change_pct": -0.91
    },
    "meta": {
        "timestamp": "2026-06-09T03:03:44.899Z",
        "request_id": "2ce8245c-ca16-4cb7-b6a7-299fe0ed0562"
    },
    "status": "ok",
    "message": "Pair retrieved successfully",
    "success": true
}
```

#### `GET /v1/strength` — Full currency strength ranking

**Parameters:**
- `period` (query, optional, string) — 1d | 7d | 2w | 1m | 3m Example: `7d`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/currencystrength-api/v1/strength?period=7d"
```

**Response:**
```json
{
    "data": {
        "count": 30,
        "period": "7d",
        "ranking": [
            {
                "name": "Philippine Peso",
                "rank": 1,
                "currency": "PHP",
                "strength": 1.251
            },
            {
                "name": "Hong Kong Dollar",
                "rank": 2,
                "currency": "HKD",
                "strength": 1.165
            },
            {
                "name": "United States Dollar",
                "rank": 3,
                "currency": "USD",
                "strength": 1.15
            },
            {
                "name": "Chinese Yuan",
                "rank": 4,
                "currency": "CNY",
                "strength": 0.891
            },
            {
                "name": "Japanese Yen",
                "rank": 5,
                "currency": "JPY",
                "strength": 0.838
            },
            {
                "name": "Turkish Lira",
                "rank": 6,
                "currency": "TRY",
                "strength": 0.684
            },
            {
                "name": "Mexican Peso",
                "rank": 7,
                "currency": "MXN",
                "strength": 0.636
            },
            {
                "name": "Thai Baht",
                "rank": 8,
                "currency": "THB",
                "strength": 0.48
            },
            {
                "name": "Czech Koruna",
                "rank": 9,
       
…(truncated, see openapi.json for full schema)
```

### Meta

#### `GET /v1/meta` — Service metadata

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/currencystrength-api/v1/meta"
```

**Response:**
```json
{
    "data": {
        "source": "ECB daily reference rates via Frankfurter (live)",
        "periods": [
            "1d",
            "7d",
            "2w",
            "1m",
            "3m"
        ],
        "service": "currencystrength-api",
        "endpoints": {
            "GET /v1/meta": "This document.",
            "GET /v1/pair": "Cross-rate and period change for a pair (base=EUR&quote=USD, period=).",
            "GET /v1/currency": "One currency's strength, rank and per-pair changes (code=USD, period=).",
            "GET /v1/strength": "Full currency strength ranking for a period (period=1d|7d|2w|1m|3m)."
        },
        "description": "Live currency strength meter computed from ECB reference rates (Frankfurter): ranks 30+ currencies by their average move against the whole basket over a period. Get the full strength ranking, one currency's strength + per-pair changes, or a pair's cross-rate and change. Live, no key. Distinct from raw exchange-rate APIs.",
        "currencies_live": 30
    },
    "meta": {
        "timestamp": "2026-06-09T03:03:45.138Z",
        "request_id": "15e51639-a097-4a3d-a562-7d5fe5615b3c"
    },
    "status": "ok",
    "message": "Meta",
    "success": true
}
```


---
Marketplace page: https://www.oanor.com/api/currencystrength-api
OpenAPI spec: https://www.oanor.com/api/currencystrength-api/openapi.json