Question 1

What does the .env validator check?

Accepted Answer

It parses your .env file line-by-line and flags: invalid identifiers (must match [A-Za-z_][A-Za-z0-9_]*), missing equals signs, duplicate keys (with line numbers for the duplicate and the first definition), unterminated single or double quotes, empty values that look unintentional, trailing whitespace on keys, and likely-secret patterns (API_KEY, SECRET, TOKEN, PASSWORD, PRIVATE_KEY) for visibility.

Question 2

Is my .env file uploaded to a server?

Accepted Answer

No. The validator runs 100% in your browser using vanilla JavaScript. Your file never leaves your machine. Open DevTools → Network tab and you'll see zero upload requests.

Question 3

What's a valid .env key name?

Accepted Answer

A valid key starts with a letter (A–Z, a–z) or underscore, followed by letters, digits, or underscores. Examples: DATABASE_URL, API_KEY, _PRIVATE, port_2. Invalid: 1FOO (starts with digit), FOO-BAR (dash not allowed), FOO BAR (space not allowed).

Question 4

What about values with spaces — should I quote them?

Accepted Answer

Yes. If a value contains spaces or special characters, wrap it in double or single quotes. The validator flags unquoted values containing spaces as warnings because most parsers will truncate at the first whitespace, which is rarely what you want.