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What are environment variables

Store keys and settings safely and reuse them across your project.

Steps at a glance

1. Create an environment variable for a key or URL.
2. Use it in your integrations and APIs.
3. Keep different values per environment.

What an environment variable is

An environment variable is a named value (like RESEND_API_KEY) that you can use across your project without pasting the value everywhere.

When to use them

• API keys (keep them private)
• Base URLs
• IDs that change between environments

How to use them

1. Create the variable in your project settings.
2. Reference it wherever the value is needed (integrations, APIs, or other settings).

Common pitfalls

You pasted a key directly into the interface

• Keep keys in environment variables and use them from Data & API where possible.

Related guides

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