T3 Env with Zod

Use T3 Env to validate and type your environment variables with Zod, with correct client/server separation and framework-aware runtime env handling.

Workflow

1. Identify the target framework.
2. Choose the correct createEnv variant and runtime strategy.
3. Apply Zod patterns that are safe for env strings.
4. Add build-time validation where possible.
5. Use presets instead of hand-maintaining platform vars.

Decision Tree

Is this Next.js (16+)?
  |-- Yes → use @t3-oss/env-nextjs
  |     |-- Use experimental__runtimeEnv (usually client vars only)
  |     '-- Validate on build → import env in next.config.ts
  |
  '-- Is this Vite?
        '-- Yes → use @t3-oss/env-core
              |-- clientPrefix: "VITE_"
              '-- runtimeEnv: import.meta.env

References

• references/nextjs.md
• references/core.md
• references/zod.md
• references/presets.md
• references/pitfalls.md

Examples

Copy/paste examples live under examples/:

• examples/nextjs/nextjs-16-plus/
• examples/core/vite-import-meta-env/