Developer Utility
Environment Variable Comparator
Compare .env files across environments, identify missing configuration keys, and detect value mismatches while keeping values out of comparison reports.
Three environments. One clear picture.
Compare .env configurations across development, staging, and production without exposing credential values in results.
Comparison runs in your browser. Values are hidden in reports. Avoid pasting real production secrets into any website unless you trust its code and hosting.
Configuration comparison matrix
Key presence and value consistency across environments.
| Variable | Development | Staging | Production | Status |
|---|---|---|---|---|
API_URL | PresentLine 2 | PresentLine 2 | PresentLine 2 | Values differ |
DATABASE_URL | PresentLine 4 | PresentLine 4 | PresentLine 4 | Values differ |
DEBUG | PresentLine 3 | PresentLine 3 | PresentLine 3 | Values differ |
FEATURE_FLAG | PresentLine 5 | PresentLine 5 | PresentLine 5 | Identical |
TOKEN | PresentLine 6 | PresentLine 6 | Missing | Missing key |
Parsing and duplicate-key warnings
This comparator checks literal values without expanding variable references. Duplicate definitions are reported and the first definition is used for comparison. Reports exclude values, but variable names themselves may be sensitive.
Quick Answer
What is an environment variable comparator?
An environment variable comparator checks configuration files for differences between development, staging, and production. It identifies missing keys, differing values, and duplicate definitions that may cause inconsistent application behavior.
How It Works
How to compare .env files
Paste each environment configuration into its editor. The tool parses KEY=value assignments, then builds a comparison matrix showing whether each variable is present and whether its values match across all three environments. Download a sanitized JSON report when you need to share the results.
Example
Example of an environment mismatch
Suppose development defines DEBUG=true, staging defines DEBUG=false, and production omits DEBUG entirely. The comparator flags the missing production key and shows which environments contain the variable, without displaying its value in the results matrix.
FAQ
Frequently asked questions
Can I compare three .env files?
Yes. The tool compares development, staging, and production configurations side by side.
Does the tool reveal environment variable values?
Values are used locally for comparison but are not included in the matrix or exported JSON report. The input editors can be masked.
Does it detect duplicate environment variables?
Yes. Duplicate definitions are reported with their line numbers. The first valid definition is used during comparison.
Are my .env files uploaded?
No. The comparison logic runs in your browser and does not require uploading the input to a server.
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