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How to create currency converter in javascript

Hello, guys In this tutorial we will try to solve the mentioned query. and also we will learn how to create a currency converter in JavaScript

Common Query

  1. How to make a currency converter
  2. How to use frankfurter free API
  3. How to create API based application

What is Currency Converter?

A currency converter is a software, that is designed to convert a currency into another to check its corresponding value. They do so by connecting to a database of current currency exchange value.
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Currency Converter Using JavaScript Step By Step Guide

To make a currency converter in javascript we use frankfurter API this is an open-source, simple, and lightweight API for current and historical foreign exchange (forex) rates published by the European Central Bank.

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Read more about frankfurter API

First, we need to create two files index.html and style.css then we need to do code for it.


Add below code inside index.html

<!DOCTYPE html>
<html lang="en">

  <meta charset="UTF-8" />
  <title>How to create currency converter</title>
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <meta http-equiv="X-UA-Compatible" content="ie=edge" />
  <link rel="stylesheet" href="style.css" />
  <link href="" rel="stylesheet">
  <link rel="stylesheet" href="">
  <script src=""></script>

  <div class="currency-row-outer">
    <div class="currency-converter">
      <h2>Currency Converter</h2>

      <div class="field grid-50-50">
        <div class="colmun col-left">
          <input type="number" class="form-input" id="number" placeholder="00000">
        <div class="colmun col-right">
          <div class="select">
            <select name="currency" class="currency" onchange="updatevalue()"></select>

      <div class="field grid-50-50">
        <div class="colmun col-left">
          <input type="text" class="form-input" id="output" placeholder="00000" disabled>
        <div class="colmun col-right">
          <div class="select">
            <select name="currency" class="currency" onchange="updatevalue()"></select>


    const select = document.querySelectorAll('.currency');
    const number = document.getElementById("number");
    const output = document.getElementById("output");

    fetch('').then((data) => data.json())
      .then((data) => {

    function display(data) {
      const entries = Object.entries(data);
      for (var i = 0; i < entries.length; i++) {
        select[0].innerHTML += `<option value="${entries[i][0]}">${entries[i][0]} : ${entries[i][1]}</option>`;
        select[1].innerHTML += `<option value="${entries[i][0]}">${entries[i][0]} : ${entries[i][1]}</option>`;

    function updatevalue() {
      let currency1 = select[0].value;
      let currency2 = select[1].value;

      let value = number.value;

      if (currency1 != currency2) {
        convert(currency1, currency2, value);
      } else {
        alert("Choose Diffrent Currency");

    function convert(currency1, currency2, value) {
      const host = "";

        .then((val) => val.json())
        .then((val) => {
          output.value = Object.values(val.rates)[0];


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Then we need to add code for style.css which code I provide in the below screen.

/*Start Currency Converter*/
* {
    padding: 0;
    margin: 0;
    font-family: 'IBM Plex Sans', sans-serif;

body {
    height: 100vh;
    width: 100vw;
    overflow-x: hidden;

.currency-row-outer {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;

.currency-converter {
    width: 100%;
    max-width: 480px;
    text-align: center;

select {
    color: #363636;
    font-size: 1rem;
    height: 2.3em;
    border-radius: 4px;
    max-width: 100%;
    width: calc(100% - 15px);
    margin: auto;
    outline: 0;
    background: #fff;
    border-color: #dbdbdb;
    padding-left: 15px;
    border: 1px solid #00000057;
    box-shadow: inset 0 0.0625em 0.125em rgb(10 10 10 / 5%);
    -webkit-appearance: none;

.field.grid-50-50 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-gap: 15px;

.currency-converter .colmun {
    margin-bottom: 15px;

select.currency {
    border-color: #3273dc;
    width: 100%;
    height: 100%;
    cursor: pointer;
    font-size: 1em;
    max-width: 100%;
    outline: 0;
    display: block;

.currency-converter .select {
    position: relative;
    height: 100%;

h2 {
    padding-bottom: 30px;

.currency-converter .select:after {
    transform: rotate(-45deg);
    transform-origin: center;
    content: "";
    border: 3px solid rgba(0, 0, 0, 0);
    border-radius: 2px;
    border-top: 0;
    border-right: 0;
    display: block;
    height: 0.525em;
    width: 0.525em;
    z-index: 4;
    position: absolute;
    top: 50%;
    right: 1.125em;
    margin-top: -0.4375em;

.select:not(:hover)::after {
    border-color: #3273dc;

.select:hover::after {
    border-color: #363636;
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Currency converter in javascript video output:

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