Validate .env

Check .env assignments for syntax, duplicates, quotes, and required names.

freeworks offlinenothing uploaded

Tool.env Validator

Input

Output

—

Put this on your own site

The frame below runs the same code as this page, in the reader's own browser. Nothing is sent to us, and nothing is sent to you.

AccentBackground

Pick a dark background and the text and panels follow it, so the frame stays readable on a dark page.

How it works

Assignments are parsed and checked for key syntax, duplicate names, missing values, quote balance, and optional required-key lists. The validator reports findings without mutating the process environment.

Syntax checks catch portable dotenv mistakes.
Required names remain project-defined.

Worked example

Validate .env file

Check for common issues like missing values and duplicates

Input

											API_KEY=abc
API_KEY=xyz
DB_URL=
INVALID KEY=value

Output

												# .env Validation Report

Variables found: 4
Errors: 1
Warnings: 4

## Errors
  - Line 4: Invalid key name "INVALID KEY" - use only letters, numbers, and underscores

## Duplicate Keys
  - Line 2: Duplicate key "API_KEY"

## Warnings
  - Line 1: "API_KEY" appears to be a secret but has a short value
  - Line 2: "API_KEY" appears to be a secret but has a short value
  - Line 4: "INVALID KEY" appears to be a secret but has a short value

When to use this

CI onboarding, deployment scripts, and local startup checks validate env files.

Edge cases

Duplicate keys hide earlier values under loader precedence.
An empty value differs from a missing key.
A quoted hash is data while an unquoted hash starts a comment.

References

dotenv