Compare environment files without uploading secrets. Paste an example file, staging config, production config, or CI variables to find missing keys, changed values, empty variables, and extra settings before a deploy.
The merge output is useful when bootstrapping a new environment, syncing .env.example, or checking whether a secret rotation accidentally removed required keys. Values stay in the browser.
Right overrides left treats the target file as authoritative for duplicate keys. Left overrides right preserves baseline values. Right fills non-empty values is useful when the target should supply only values that are present, without replacing a baseline value with an empty assignment.
The report helps find structural differences, but it cannot confirm that a token is valid, a URL is reachable, or a service accepts the merged configuration. Inspect changed and empty values, then validate the output in the intended runtime before replacing an existing environment file.
Related tools: .env to JSON · JSON to .env