Vercel Global Config
Global Config is available on all plans
A Global Config is a global data store that enables experimentation with feature flags, A/B testing, critical redirects, and IP blocking. It enables you to read data in the region closest to the user without querying an external database or hitting upstream servers.
With Vercel's optimizations, you can read Global Config data at negligible latency. The vast majority of your reads will complete within 15ms at P99, or often less than 1ms.
You can use a Global Config in Middleware and Vercel Functions.
Global Configs are great for data that is accessed frequently and updated infrequently. Here are some examples of storage data suitable for Global Config:
Critical redirects: When you need to redirect a URL urgently, Global Configs offer a fast solution that doesn't require you to redeploy your website. With Middleware, you can read from your Global Config to redirect users visiting incorrect URLs. For an example, see the Maintenance Page template.
Alternatively, use the Vercel WAF to configure a Redirect action based on specific conditions. For more details, check the emergency redirect example.
Malicious IP and User Agent blocking: Store a set of malicious IPs in your Global Config, then block them upon detection without invoking upstream servers
You can create and manage your Global Config from either Vercel REST API or Dashboard. You can scope your Global Configs to your Hobby team or team, and connect them to as many projects as you want.
To get started, see our quickstart.
Deploy a Global Config Template
If you'd like to know whether or not Global Config can be integrated into your workflow, it's worth knowing the following:
- You can have one or more Global Configs per Vercel account, depending on your plan as explained in Limits
- You can use multiple Global Configs in one Vercel project
- Each Global Config can be accessed by multiple Vercel projects
- Global Configs can be scoped to different environments within projects using environment variables
- Global 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
See our Global Config limits docs to learn more
There are alternative solutions to Global Config for handling A/B testing, feature flags, and IP blocking. The following table lays out how those solutions compare to Global Config:
| Global Config vs alternatives | Read latency | Write latency | Redeployment required | Added risk of downtime |
|---|---|---|---|---|
| Global Config | Ultra-low | Varies | No | No |
| Remote JSON files | Varies | Varies | No | Yes |
| Embedded JSON files | Lowest | Highest | Yes | No |
| Environment Variables | Lowest | Highest | Yes | No |
To learn about Global Config limits and pricing, see our Global Config limits docs.
Was this helpful?