Why WebOTP API is a Game-Changer for Your React App

 import React, { useState } from 'react';  function ManualOtpForm({ onSubmit }) {   const [otp, setOtp] = useState('');    const handleSubmit = (e) => {     e.preventDefault();     // Basic validation     if (otp.length === 6 && /^[0-9]+$/.test(otp)) {       onSubmit(otp);     } else {       alert('Please enter a valid 6-digit OTP.');     }   };    return (     <form onSubmit={handleSubmit}>       <label htmlFor="otp-input">Enter your 6-digit code:</label>       <input         id="otp-input"         type="text"         inputMode="numeric"         autoComplete="one-time-code"         value={otp}         onChange={(e) => setOtp(e.target.value)}         maxLength="6"       />       <button type="submit">Verify Code</button>     </form>   ); } 

How to Implement the WebOTP API in Your React App

Alright, let's get to the fun part. Integrating WebOTP is surprisingly straightforward, especially when encapsulated in a custom React hook for reusability.

Step 1: The SMS Message Format (This is Crucial!)

The API will only work if your SMS message follows a specific format. The message must contain the website's origin, preceded by @, and the OTP code, preceded by #.

The format is:

Your verification code is #123456.

@your-app-domain.com #123456

The human-readable text can be anything. The last line, containing the origin and the code, is what the browser looks for. For a site at https://app.example.com, the SMS must include @app.example.com.

Step 2: Creating a useWebOTP Custom Hook

A custom hook is the perfect way to manage the API's lifecycle and state. It keeps our components clean and the logic centralized.

 import { useEffect, useState } from 'react';  export const useWebOTP = () => {   const [otp, setOtp] = useState('');   const [isSupported, setIsSupported] = useState(false);   const [error, setError] = useState(null);    useEffect(() => {     if ('OTPCredential' in window) {       setIsSupported(true);       const ac = new AbortController();        navigator.credentials.get({         otp: { transport: ['sms'] },         signal: ac.signal,       }).then(otpCredential => {         if (otpCredential) {           setOtp(otpCredential.code);         }       }).catch(err => {         // The user likely aborted the request or it timed out.         // This is not a critical error, so we can often ignore it.         console.warn(err);         setError(err);       });        // Cleanup function to abort the request if the component unmounts       return () => {         ac.abort();       };     } else {       setIsSupported(false);     }   }, []); // Empty dependency array means this runs once on mount    return { otp, isSupported, error }; }; 

Step 3: Using the Hook in Your Component

Now, we can import and use our new hook in the verification component. We'll combine it with our manual input as a graceful fallback.

 import React, { useState, useEffect } from 'react'; import { useWebOTP } from './useWebOTP'; // Assuming the hook is in this file  function VerificationForm({ onSubmit }) {   const [manualOtp, setManualOtp] = useState('');   const { otp: webOtp, isSupported } = useWebOTP();    // When the WebOTP API provides a code, update our state   useEffect(() => {     if (webOtp) {       setManualOtp(webOtp);       // Optional: Automatically submit the form       onSubmit(webOtp);     }   }, [webOtp, onSubmit]);    const handleSubmit = (e) => {     e.preventDefault();     if (manualOtp.length === 6) {       onSubmit(manualOtp);     } else {       alert('Please enter a valid 6-digit code.');     }   };    return (     <form onSubmit={handleSubmit}>       <h3>Verify Your Identity</h3>       {isSupported ? (         <p>Waiting to automatically detect the code from your SMS...</p>       ) : (         <p>Please enter the code sent to your device.</p>       )}       <input         id="otp-input"         type="text"         inputMode="numeric"         autoComplete="one-time-code" // Important for accessibility and password managers         value={manualOtp}         onChange={(e) => setManualOtp(e.target.value)}         maxLength="6"         required       />       <button type="submit" disabled={manualOtp.length !== 6}>         Verify       </button>     </form>   ); } 

This component now intelligently handles both scenarios. If WebOTP is supported, it listens for the code. If not, or if the user cancels the prompt, it functions as a standard manual input form. This is the essence of progressive enhancement.

Browser Compatibility: The Reality Check

As with many new web APIs, browser support is a key consideration. The WebOTP API is not universally available, so a fallback is essential.

Browser	Support Status
Chrome for Android (84+)	✅ Supported
Safari on iOS / iPadOS (14+)	✅ Supported (via autoComplete="one-time-code")
Desktop Browsers (Chrome, Firefox, Edge, Safari)	❌ Not Supported
Firefox for Android	❌ Not Supported

The good news is that it covers a massive portion of the mobile web user base. For iOS/iPadOS, while it doesn't use the WebOTP JavaScript API directly, setting autoComplete="one-time-code" on your input triggers a similar native behavior where the code appears above the keyboard for easy insertion, provided your SMS is formatted correctly.

Is It Secure? Unpacking the Safety Features

Handing over SMS data to a website sounds risky, but the API was designed with security as a top priority:

• Origin-Bound: This is the most important feature. The API will only trigger for an SMS that explicitly mentions the domain of the website that is currently open. A message for @bank.com cannot be read by @evil-phishing-site.com.
• User Consent is Mandatory: The browser will always prompt the user for permission before sharing the code. It cannot be read silently in the background.
• Transient and Focused: The navigator.credentials.get() call is a one-time request. It doesn't grant the website perpetual access to your SMS inbox. It only looks for a single, matching OTP when invoked.

Conclusion: Why You Should Adopt WebOTP Today

The WebOTP API is more than just a cool technical trick; it's a fundamental improvement to a critical part of the user journey. By removing the clunky, manual step of entering an SMS code, you directly address a major point of user friction.

For your React application, this translates to:

• ✨ Dramatically Better User Experience: Users will love the seamless, one-tap flow.
• 📈 Higher Conversion Rates: Reducing friction during signup and login directly impacts user retention and completion rates.
• 🔒 Enhanced Security Perception: A smooth, professional authentication flow builds trust in your platform.

Implementing it with a custom hook and a graceful fallback is a low-effort, high-reward task. You cater to users on modern mobile browsers while ensuring everyone else still has a perfectly functional experience. So, the next time you're building a feature that uses SMS verification, give the WebOTP API a try. Your users will thank you for it.