Add Rate Limiting with Vercel

This guide is a comprehensive walkthrough to handle rate limiting using the Vercel Web Application Firewall (WAF). We will discuss the necessity of rate limiting, understanding Vercel and its features like Vercel WAF and review a resource on implementing rate limiting with Vercel WAF.

Rate limiting is a technique for controlling network traffic. It sets a limit on how many requests a client can make to a server in a specific period.

1. Ensure uptime of your services: Rate limiting protects your services from being overwhelmed by excessive requests. By controlling the number of requests, you can maintain the optimal performance of your service and ensure its availability.
2. Control billing: Rate limiting helps manage and control your billing costs by preventing unforeseen spikes in usage, particularly important when using services that charge by the request.
3. Prevent malicious usage: Rate limiting is essential when using AI providers and Large Language Models (LLMs). Rate limiting can protect your service from malicious usage or abuse, such as DDoS attacks.
4. Add differentiation of product usage based on plan: Rate limiting can be used to create usage tiers. For example, free users might be limited to a certain number of requests per day, while premium users might have a higher limit.

Vercel's frontend cloud gives developers frameworks, workflows, and infrastructure to build a faster, more personalized web.

We are the creators of Next.js, the React framework, and have zero-configuration support for all major frontend frameworks.

Vercel WAF allows you to monitor and control the internet traffic to your site through IP blocking, custom rules and managed rulesets.

With Vercel WAF, you can configure specific rules to log, deny, challenge, bypass, or rate limit traffic to your site. When you apply the configuration, it takes effect immediately and does not require re-deployment.

1. Add a rate limiting custom rule to your Vercel project with the Rate Limit API Requests Firewall Rule template or the Get Started documentation
2. In the Configure section, set an If condition with the following values for the 3 drop-down fields: Request Path, Equals and the value of the request path that you would like to rate limit such as api/rate-limit-endpoint
3. Set the Then action to Rate Limit and follow the remaining steps from the Get started documentation