Login with Amazon Technology Intelligence

What is Login with Amazon?

Login with Amazon (LWA) is Amazon's OAuth 2.0 authentication service enabling users to sign into third-party websites and apps using their Amazon account credentials. With 300+ million active Amazon customer accounts globally, LWA provides a substantial user base for e-commerce and retail applications.

Beyond basic authentication, Login with Amazon can retrieve shipping addresses and payment methods from Amazon accounts (with user permission), enabling pre-filled checkout experiences without users re-entering information. This is particularly powerful for e-commerce sites.

LWA integrates with Amazon Pay, allowing authenticated users to complete purchases using stored Amazon payment methods. This combination of identity and commerce makes Login with Amazon especially valuable for online retailers.

Login with Amazon Architecture

OAuth 2.0 Scopes: profile (user_id, name, email), postal_code (shipping postal code), profile:user_id (minimal identity). Additional scopes for Amazon Pay integration.

Access Tokens: Tokens valid for 1 hour. Refresh tokens enable long-lived access. Server-side and client-side flows supported.

SDK Options: JavaScript SDK for web, iOS SDK, Android SDK, and Fire OS SDK. Server-side implementations use REST API directly.

Amazon Pay Integration: payments:widget scope enables address and payment widgets. Users select from saved Amazon addresses/cards without entering data.

Alexa Integration: Skills can use LWA for account linking. Users authorize Alexa skills to access their account on your service.

Regional Availability: Works globally but tied to regional Amazon accounts (amazon.com, amazon.co.uk, amazon.de, amazon.co.jp). Users sign in with their regional account.

Login with Amazon Use Cases

E-commerce Checkout: Pre-fill shipping addresses from Amazon profiles. Users trust Amazon with their address data; sharing with retailers feels safer.

Amazon Pay Merchants: Sites accepting Amazon Pay use LWA as authentication gateway. Unified identity across browsing and purchasing.

Alexa Skills: Smart home, productivity, and commerce skills link user accounts via LWA. "Alexa, order from [your brand]" requires account linking.

Fire TV Apps: Streaming and gaming apps on Fire TV use LWA for account creation. Amazon account holders sign in instantly.

Kindle/Audible Integration: Services offering digital content use LWA to sync with users' Amazon digital libraries.

AWS Service Integration: Applications on AWS can combine LWA with Cognito for authentication that works with Amazon consumer accounts.

Login with Amazon Implementation

JavaScript SDK

<script src="https://assets.loginwithamazon.com/sdk/na/login1.js"></script>

<a href="#" id="LoginWithAmazon">
    <img src="https://images-na.ssl-images-amazon.com/images/G/01/lwa/btnLWA_gold_156x32.png">
</a>

<script>
window.onAmazonLoginReady = function() {
    amazon.Login.setClientId('YOUR_CLIENT_ID');
};

document.getElementById('LoginWithAmazon').onclick = function() {
    amazon.Login.authorize({scope: 'profile'}, function(response) {
        if (response.access_token) {
            amazon.Login.retrieveProfile(response.access_token, function(profile) {
                console.log('Name:', profile.Name);
                console.log('Email:', profile.PrimaryEmail);
                // Create account on your server
            });
        }
    });
    return false;
};
</script>

Server-Side Token Verification

const response = await fetch('https://api.amazon.com/user/profile', {
    headers: { 'Authorization': `Bearer ${accessToken}` }
});
const profile = await response.json();
// { user_id, email, name, postal_code }

Login with Amazon Benefits

E-commerce Trust: Amazon is synonymous with online shopping. Users trust sharing commerce-related data (addresses, payments) with Amazon more than other providers.

Address Pre-fill: Access to verified shipping addresses reduces checkout friction. Fewer form fields = higher conversion rates.

Amazon Pay Synergy: Combined authentication and payment flow. Users authenticate once, purchase with stored payment methods.

Prime Demographics: Amazon users skew toward active online shoppers. High purchase intent audience for e-commerce sites.

Alexa Ecosystem: Account linking enables voice commerce and smart home integrations. Growing channel for customer engagement.

Global Reach: Works with regional Amazon accounts worldwide. Localized experience for US, UK, Germany, Japan, and more.

Free to Use: No costs for authentication. Only Amazon Pay transactions have fees (similar to other payment processors).