Web Crypto API RSA-OAEP Generate Keys and Perform Encryption/Decryption

The Demo

This is the web cryptography api example of performing rsa oaep encryption decryption

Input Text Output
Generated IV
RSA-OAEP Public Key (JWK) :
RSA-OAEP Private Key (JWK):

<h2 class="mt-4"><a id="Javascript_example_of_using_webcrypto_api_RSAOAEP_10"/>webcrypto api RSA-OAEP Javascript example</h2>
<p>Generate the RSA-OAEP 2048 bit Keys using SHA-256 Algorithms</p>
<pre><code class="html">window.crypto.subtle.generateKey({
                    name: "RSA-OAEP",
                    modulusLength: 2048, //can be 1024, 2048, or 4096
                    publicExponent: new Uint8Array([0x01, 0x00, 0x01]),
                    hash: {
                        name: "SHA-256"
                    }, //can be "SHA-1", "SHA-256", "SHA-384", or "SHA-512"
                true, //whether the key is extractable (i.e. can be used in exportKey)
                ["encrypt", "decrypt"] //must be ["encrypt", "decrypt"] or ["wrapKey", "unwrapKey"]
<p>Sample Export keys to display the RSA public private key in JWK format (You can skip this step) This is for demo purpose, which i showed in UI.</p>
<pre><code class="html">window.crypto.subtle.exportKey("jwk", key.publicKey).then(
                    function(keydata) {
                        publicKeyhold = keydata;
                        publicKeyJson = JSON.stringify(publicKeyhold);
                        document.getElementById("rsapublic").value = publicKeyJson;
window.crypto.subtle.exportKey("jwk", key.privateKey).then(
                    function(keydata) {
                        privateKeyhold = keydata;
                        privateKeyJson = JSON.stringify(privateKeyhold);
                        document.getElementById("rsaprivate").value = privateKeyJson;
<p>RSA-OAEP Encryption Example</p>
<pre><code class="html">window.crypto.subtle.encrypt({
                            name: "RSA-OAEP",
                            iv: iv,
                        publicKey, //from generateKey or importKey above
                        asciiToUint8Array(plainText) //ArrayBuffer of data you want to encrypt
                    .then(function(encrypted) {
                        //returns an ArrayBuffer containing the encrypted data
                        document.getElementById("cipherText").value = bytesToHexString(encrypted);
                        document.getElementById("salt").value = bytesToHexString(iv);
                    .catch(function(err) {
                        console.error(err);
<p>RSA-OAEP decryption Example</p>
<pre><code class="html">var cipherText = document.getElementById("cipherText").value;
    window.crypto.subtle.decrypt({
                name: "RSA-OAEP",
                iv: iv
            privateKey, //from generateKey or importKey above
            hexStringToUint8Array(cipherText) //ArrayBuffer of the data
        .then(function(decrypted) {
            alert(bytesToASCIIString(decrypted));
        .catch(function(err) {
            console.error(err);
Download the sample code <a href="https://leanpub.com/cryptojs">here </a>
Next Reading <a href="window-crypto-aes.jsp">Perform AES Encryption Using importKey Method </a>