Edge Config Overview
An Edge Config is a key-value data store associated with your Vercel account. It enables you to read data at the edge without querying an external database.An Edge Config is a key-value data store associated with your Vercel account. It enables you to read data at the edge without querying an external database. You can use it to check feature flags, initiate redirects, or block malicious IPs at the speed of the Edge, without hitting upstream servers.
With Vercel's optimizations, you can read Edge Config data at negligible latency. The vast majority of your reads will complete within 15ms at P99, or as low as 0ms in some scenarios.
You can use an Edge Config in Edge Functions, Edge Middleware, and Serverless Functions.
You can read your Edge Config using the Edge Config client SDK or the Vercel API. It is recommended to use the client SDK or call the Edge Config endpoint when what matters the most to you is the speed of the requests. In this case, your data is globally replicated, your requests have no rate limits and are inexpensive.
If you instead use the Vercel API, you always get the latest values of the data but you do not benefit from our optimizations and it is slower to read. If this is your use case, be aware that the endpoint is not globally replicated, rate limits apply and they are more expensive.
You can only manage the config using the Vercel Dashboard or API.
- You can have one or more Edge Configs per Vercel account, depending on your plan as explained in Limits
- You can use multiple Edge Configs in one Vercel project
- Each Edge Config can be accessed by multiple Vercel projects
- Edge Configs can be scoped to different environments within projects using environment variables
- Edge Config access is secure by default. A read access token is required to read from them, and an API token is required to write to them
Edge Configs are great for data that is accessed frequently and updated infrequently. Find examples of storage data suitable for Edge Config:
Feature flags and A/B testing: Experiment with A/B testing by storing feature flags in your Edge Config. Fetching such data from Edge Config rather than a database can cut page loads by hundreds of milliseconds. Deploy the template
Critical redirects: When you need to redirect a URL urgently, Edge Configs offer a fast solution that doesn't require you to redeploy your website. Using Edge Middleware, you can read from your Edge Config to redirect users when they visit bad URLs. Deploy the template
Malicious IP and User Agent blocking: Store a set of malicious IPs in your Edge Config, then block them upon detection without invoking upstream servers