When Access Token Gets Snapped, Refresh Token Assembles a New One

Introduction

Just like Thanos 🧤 snapped half the Avengers out of existence, your access token won’t live forever. Luckily, refresh tokens assemble to save the day. 😎

What is an Access Token? 🔒

An Access Token is a short-lived credential used to access protected APIs. It proves the user is authenticated.

• Used in: API requests (in headers)

• Expires in: Minutes to an hour

• Risk: Safer because it’s short-lived

What is a Refresh Token? 🔃

A Refresh Token is a long-lived token that gets a new access token when the old one expires. It’s not sent with every API request.

• Used in: Token renewal

• Expires in: Hours to days

• Risk: Must be stored securely (can be abused if stolen)

Why Not Just Use a Long-Lived Access Token? 🧠🤔

Long-lived access tokens increase the risk of misuse if stolen. If a token with a lifespan of 30 days is compromised, an attacker gets prolonged access. Short-lived access tokens + refresh tokens offer a balance between security and usability.

Comparison Table ⚡

Best Practices 👌😍

• Store access tokens in memory

• Store refresh tokens in HTTP-only cookies

• Always use HTTPS

• Rotate refresh tokens regularly

• Never store tokens in localStorage

Real-World Analogy 🥸🎼

Access token = concert ticket
Refresh token = your ID card to get another ticket when the first expires

Final Thoughts 🌜⏮️

Using access and refresh tokens together is a modern, secure approach to authentication. It enhances user experience by minimising logins while keeping your app safer. Implementing them properly can help you build scalable and secure authentication systems.