What's the difference between .env and .env.example mode?

In .env mode, each row's actual value is written out (quoted automatically if it contains spaces, quotes, or a #). In .env.example mode, every value is blanked (KEY=) so the file documents which variables are required without leaking real secrets, exactly the convention most teams commit to version control instead of the real .env.

Why does the framework choice matter if it's just a comment?

Several frameworks only expose a subset of environment variables to client-side code based on a naming convention, Vite requires a VITE_ prefix and Next.js requires NEXT_PUBLIC_ for anything the browser bundle can read. The generated note is a reminder of that convention so you don't accidentally expect a server-only variable to be readable in browser code (or worse, accidentally prefix a secret so it leaks to the client).

How do sections work?

Each row can have an optional section label (e.g. "Database", "Auth", "Third-party APIs"); rows sharing the same section are grouped together under a single `# Section` comment header, in the order sections first appear, making longer .env files easier to scan.

Does this tool validate variable names?

Yes. Each key must match standard environment variable naming (letters, digits, underscores, not starting with a digit); anything else is rejected with an error naming the offending row before any output is generated.

.env File Generator - Build .env / .env.example Files

Overview

Introduction

Every project ends up with a .env file, and almost every project also ends up needing a matching .env.example for onboarding, two files that are supposed to stay in sync but usually drift the moment someone adds a variable in a hurry.

This tool generates both from the same structured input: fill in your keys, values, comments, and sections once, then toggle example mode to produce the safe-to-commit version with values blanked out.

What Is .env File Generator?

A generator for .env-style files: a repeatable list of rows, each with a KEY, a VALUE, an optional inline comment, and an optional section label used to group related variables under a shared header.

A framework preset (Node, Vite, Next.js, Django, Rails) adds a short note at the top of the file about how that framework loads env vars and which prefix convention (if any) controls client-side exposure.

How .env File Generator Works

Rows are grouped by their section label (defaulting to "General" when left blank), preserving the order sections first appear, and each group is emitted under a `# Section` comment header.

Values containing whitespace, a quote character, or a `#` are automatically wrapped in double quotes (with internal quotes escaped) so the resulting line parses correctly; in example mode, every value is blanked regardless of its real content.

When To Use .env File Generator

Use it when scaffolding a new project's .env and .env.example together, so the two files are guaranteed to list the same keys in the same order.

It's also useful for documenting an existing project's required environment variables in a clean, sectioned .env.example for new contributors.

Often used alongside .env File Validator and Secrets Manager Config Generator.

Features

Advantages

Generates .env and .env.example from the same input, keeping them in sync by construction rather than by manual discipline.
Groups variables into labeled sections, making a file with many variables far easier to navigate.
Automatically quotes values that would otherwise break simple .env parsers (spaces, quotes, `#`).

Limitations

Doesn't detect or warn about duplicate keys across rows, that check lives in the separate .env File Validator tool.
The framework note is informational only; it doesn't enforce or rewrite prefixes (like adding VITE_ automatically) on your keys.

Examples

Next.js app with a public and a server-only variable

Input

framework: Next.js, rows: [{key: DATABASE_URL, value: postgres://localhost/app, section: Database}, {key: NEXT_PUBLIC_API_URL, value: https://api.example.com, section: API}]

Output

# Next.js environment variables
# Only variables prefixed NEXT_PUBLIC_ are exposed to the browser; all others stay server-only.

# Database
DATABASE_URL=postgres://localhost/app

# API
NEXT_PUBLIC_API_URL=https://api.example.com

Each section groups its rows under one header, and the framework note reminds you which prefix makes a variable browser-visible.

Best Practices & Notes

Best Practices

Always commit the .env.example version, never the real .env, to version control.
Keep secrets and non-secret config in the same file but use clear section labels ("Secrets", "Public config") so reviewers can tell them apart at a glance.
Regenerate .env.example whenever you add a new required variable, rather than letting it drift from the real .env used in development.

Developer Notes

Rows are grouped using a `Map<string, EnvRowInput[]>` keyed by section label, which preserves insertion order in JavaScript, so sections appear in the file in the order their first row was added, not alphabetically. Quoting is applied with a single regex test (`/[\s#"']/`) covering the characters that would otherwise break naive `KEY=VALUE` parsing or shell sourcing of the file.

.env File Generator Use Cases

Scaffolding a new project's .env and .env.example files together
Documenting a growing list of required environment variables in sectioned, readable form
Producing a framework-specific .env with the right client/server-exposure note attached as a reminder

Common Mistakes

Committing the real .env (with live secrets) instead of the blanked .env.example version to version control.
Prefixing a genuinely secret variable with a client-exposure prefix (VITE_, NEXT_PUBLIC_) by habit, which ships it straight into the browser bundle.

Tips

Run the output through the .env File Validator afterward to catch anything the generator's own checks don't cover, like values that look like numbers or booleans but are always read back as strings.

.env File Generator