How do I get currency exchange rates via an API such as Google Finance? [closed]

Answer 1

For all newbie guys searching for some hint about currency conversion, take a look at this link. Datavoila

It helped med a lot regarding my own project in C#. Just in case the site disappears, I'll add the code below. Just add the below steps to your own project. Sorry about the formatting.

const string fromCurrency = "USD";
const string toCurrency = "EUR";
const double amount = 49.95;
// For other currency symbols see http://finance.yahoo.com/currency-converter/
// Clear the output editor //optional use, AFAIK
Output.Clear();

// Construct URL to query the Yahoo! Finance API
const string urlPattern = "http://finance.yahoo.com/d/quotes.csv?s={0}{1}=X&f=l1";
string url = String.Format(urlPattern, fromCurrency, toCurrency);

// Get response as string
string response = new WebClient().DownloadString(url);

// Convert string to number
double exchangeRate =
    double.Parse(response, System.Globalization.CultureInfo.InvariantCulture);

// Output the result
Output.Text = String.Format("{0} {1} = {2} {3}",
                            amount, fromCurrency,
                            amount * exchangeRate, toCurrency);

Answer 2

Thanks for all your answers.

Free currencyconverterapi:

• Rates updated every 30 min
• API key is now required for the free server.

A sample conversion URL is: http://free.currencyconverterapi.com/api/v5/convert?q=EUR_USD&compact=y

---

For posterity here they are along with other possible answers:

1. Yahoo finance API Discontinued 2017-11-06###

Discontinued as of 2017-11-06 with message

It has come to our attention that this service is being used in violation of the Yahoo Terms of Service. As such, the service is being discontinued. For all future markets and equities data research, please refer to finance.yahoo.com.

Request: http://finance.yahoo.com/d/quotes.csv?e=.csv&f=sl1d1t1&s=USDINR=X
This CSV was being used by a jQuery plugin called Curry. Curry has since (2017-08-29) moved to use fixer.io instead due to stability issues. Might be useful if you need more than just a CSV.

2. (thanks to Keyo) Yahoo Query Language lets you get a whole bunch of currencies at once in XML or JSON. The data updates by the second (whereas the European Central Bank has day old data), and stops in the weekend. Doesn't require any kind of sign up.

http://query.yahooapis.com/v1/public/yql?q=select * from yahoo.finance.xchange where pair in ("USDEUR", "USDJPY", "USDBGN", "USDCZK", "USDDKK", "USDGBP", "USDHUF", "USDLTL", "USDLVL", "USDPLN", "USDRON", "USDSEK", "USDCHF", "USDNOK", "USDHRK", "USDRUB", "USDTRY", "USDAUD", "USDBRL", "USDCAD", "USDCNY", "USDHKD", "USDIDR", "USDILS", "USDINR", "USDKRW", "USDMXN", "USDMYR", "USDNZD", "USDPHP", "USDSGD", "USDTHB", "USDZAR", "USDISK")&env=store://datatables.org/alltableswithkeys

Here is the YQL query builder, where you can test a query and copy the url: (NO LONGER AVAILABLE)

http://developer.yahoo.com/yql/console/?q=show%20tables&env=store://datatables.org/alltableswithkeys#h=select%20*%20from%20yahoo.finance.xchange%20where%20pair%20in%20%28%22USDMXN%22%2C%20%22USDCHF%22%29

3. Open Source Exchange Rates API

Free for personal use (1000 hits per month)
Changing "base" (from "USD") is not allowed in Free account
Requires registration.
Request: http://openexchangerates.org/latest.json
Response:

   <!-- language: lang-js -->

    {
      "disclaimer": "This data is collected from various providers ...",
      "license": "all code open-source under GPL v3 ...",
      "timestamp": 1323115901,
      "base": "USD",
      "rates": {
          "AED": 3.66999725,
          "ALL": 102.09382091,
          "ANG": 1.78992886,
          // 115 more currency rates here ...
      }
    }

4. currencylayer API

Free Plan for 250 monthly hits
Changing "source" (from "USD") is not allowed in Free account
Requires registration.
Documentation: currencylayer.com/documentation

JSON Response:

   <!-- language: lang-js -->

    {
      [...]
      "timestamp": 1436284516,
      "source": "USD",
      "quotes": {
          "USDAUD": 1.345352401,
          "USDCAD": 1.27373397,
          "USDCHF": 0.947845302,
          "USDEUR": 0.91313905,
          "USDGBP": 0.647603397,
          // 168 world currencies
          }
      }

5. CurrencyFreaks API

Free Plan (1000 hits per month)
Changing 'Base' (From 'USD') is not allowed in free account
Requires registration
Data updated every 60 sec.
179 currencies worldwide including currencies, metals, and cryptocurrencies
Support (Even on the free plan) Shell,Node.js, Java, Python, PHP, Ruby, JS, C#, C, Go, Swift.
Documentation: https://currencyfreaks.com/documentation.html

Endpoint:

$ curl 'https://api.currencyfreaks.com/latest?apikey=YOUR_APIKEY'

JSON Response:

{
    "date": "2020-10-08 12:29:00+00",
    "base": "USD",
    "rates": {
        "FJD": "2.139",
        "MXN": "21.36942",
        "STD": "21031.906016",
        "LVL": "0.656261",
        "SCR": "18.106031",
        "CDF": "1962.53482",
        "BBD": "2.0",
        "GTQ": "7.783265",
        "CLP": "793.0",
        "HNL": "24.625383",
        "UGX": "3704.50271",
        "ZAR": "16.577611",
        "TND": "2.762",
        "CUC": "1.000396",
        "BSD": "1.0",
        "SLL": "9809.999914",
        "SDG": 55.325,
        "IQD": "1194.293591",
          .
          .
          .
    [179 currencies]
    }
}

6. Fixer.io API (European Central Bank data)

Free Plan for 1,000 monthly hits
Changing "source" (from "USD") is not allowed in Free account Requires registration.

This API endpoint is deprecated and will stop working on June 1st, 2018. For more information please visit: https://github.com/fixerAPI/fixer#readme)

Website : http://fixer.io/
Example request : [http://api.fixer.io/latest?base=USD][7]
Only collects one value per each day

7. European Central Bank Feed

Docs: http://www.ecb.int/stats/exchange/eurofxref/html/index.en.html#dev
Request: http://www.ecb.int/stats/eurofxref/eurofxref-daily.xml

XML Response:

   <!-- language: lang-xml -->

    <Cube>
      <Cube time="2015-07-07">
      <Cube currency="USD" rate="1.0931"/>
      <Cube currency="JPY" rate="133.88"/>
      <Cube currency="BGN" rate="1.9558"/>
      <Cube currency="CZK" rate="27.100"/>
    </Cube>

8. exchangeratesapi.io

According to the website:

Exchange rates API is a free service for current and historical foreign exchange rates published by the European Central Bank

This service is compatible with fixer.io and is really easy to use: no API key needed. For example (this uses CURL, but you can use your favourite requesting tool):

    > curl https://api.exchangeratesapi.io/latest?base=GBP&symbols=USD
    {"base":"GBP","rates":{"USD":1.264494191},"date":"2019-05-29"}

9. CurrencyApi.net

Free Plan for 1250 monthly hits
150 Crypto and physical currencies - live updates
Base currency is set as USD on free account
Requires registration.
Documentation: currencyapi.net/documentation

JSON Response:

    {
      "valid": true,
      "updated": 1567957373,
      "base": "USD",
      "rates": {
              "AED": 3.673042,
              "AFN": 77.529504,
              "ALL": 109.410403,
              // 165 currencies + some cryptos
          }
      }

10. Currency from LabStack

Website: https://labstack.com/currency
Documentation: https://labstack.com/docs/api/currency/convert
Pricing: https://labstack.com/pricing
Request: https://currency.labstack.com/api/v1/convert/1/USD/INR
Response:

```js
 {
   "time": "2019-10-09T21:15:00Z",
   "amount": 71.1488
 }
 ```

1: http://query.yahooapis.com/v1/public/yql?q=select * from yahoo.finance.xchange where pair in ("USDEUR", "USDJPY", "USDBGN", "USDCZK", "USDDKK", "USDGBP", "USDHUF", "USDLTL", "USDLVL", "USDPLN", "USDRON", "USDSEK", "USDCHF", "USDNOK", "USDHRK", "USDRUB", "USDTRY", "USDAUD", "USDBRL", "USDCAD", "USDCNY", "USDHKD", "USDIDR", "USDILS", "USDINR", "USDKRW", "USDMXN", "USDMYR", "USDNZD", "USDPHP", "USDSGD", "USDTHB", "USDZAR", "USDISK")&env=store://datatables.org/alltableswithkeys

Answer 3

The European Central Bank (ECB) also has the most reliable free feed that I know of. It contains approx 28 currencies and is updated at least daily.

http://www.ecb.int/stats/eurofxref/eurofxref-daily.xml

For more formats and tools see the ECB reference page: http://www.ecb.int/stats/exchange/eurofxref/html/index.en.html

Answer 4

I got this content from http://www.scriptarticle.com/2012/05/03/get-live-currency-rates-and-currency-conversion-using-php-and-apis/

<?php

function get_currency($from_Currency, $to_Currency, $amount) {
    $amount = urlencode($amount);
    $from_Currency = urlencode($from_Currency);
    $to_Currency = urlencode($to_Currency);

    $url = "http://www.google.com/finance/converter?a=$amount&from=$from_Currency&to=$to_Currency";

    $ch = curl_init();
    $timeout = 0;
    curl_setopt ($ch, CURLOPT_URL, $url);
    curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);

    curl_setopt ($ch, CURLOPT_USERAGENT,
                 "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");
    curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
    $rawdata = curl_exec($ch);
    curl_close($ch);
    $data = explode('bld>', $rawdata);
    $data = explode($to_Currency, $data[1]);

    return round($data[0], 2);
}

// Call the function to get the currency converted
echo get_currency('USD', 'INR', 1);

?>

Answer 5

Here are some exchange APIs with PHP example.

[ Open Exchange Rates API ]

Provides 1,000 requests per month free. You must register and grab the App ID. The base currency USD for free account. Check the supported currencies and documentation.

// open exchange URL // valid app_id * REQUIRED *
$exchange_url = 'https://openexchangerates.org/api/latest.json';
$params = array(
    'app_id' => 'YOUR_APP_ID'
);

// make cURL request // parse JSON
$curl = curl_init();
curl_setopt_array($curl, array(
    CURLOPT_URL => $exchange_url . '?' . http_build_query($params),
    CURLOPT_RETURNTRANSFER => true
));
$response = json_decode(curl_exec($curl));
curl_close($curl);

if (!empty($response->rates)) {
    // convert 150 USD to JPY ( Japanese Yen )
    echo $response->rates->JPY * 150;
}

150 USD = 18039.09015 JPY

[ Currency Layer API ]

Provides 1,000 requests per month free. You must register and grab the Access KEY. Custom base currency is not supported in free account. Check the documentation.

$exchange_url = 'http://apilayer.net/api/live';
$params = array(
    'access_key' => 'YOUR_ACCESS_KEY',
    'source' => 'USD',
    'currencies' => 'JPY',
    'format' => 1 // 1 = JSON
);

// make cURL request // parse JSON
$curl = curl_init();
curl_setopt_array($curl, array(
    CURLOPT_URL => $exchange_url . '?' . http_build_query($params),
    CURLOPT_RETURNTRANSFER => true
));
$response = json_decode(curl_exec($curl));
curl_close($curl);

if (!empty($response->quotes)) {
    // convert 150 USD to JPY ( Japanese Yen )
    echo '150 USD = ' . $response->quotes->USDJPY * 150 . ' JPY';
}

150 USD = 18036.75045 JPY

Answer 6

If you need a free and simple API for converting one currency to another, try free.currencyconverterapi.com.

Disclaimer, I'm the author of the website and I use it for one of my other websites.

The service is free to use even for commercial applications but offers no warranty. For performance reasons, the values are only updated every hour.

A sample conversion URL is: http://free.currencyconverterapi.com/api/v6/convert?q=EUR_PHP&compact=ultra&apiKey=sample-api-key which will return a json-formatted value, e.g. {"EUR_PHP":60.849184}