.env to AWS Lambda Environment Converter

AWS Lambda functions read configuration from the Environment block: a flat key-value map with strict rules — keys must be letters, digits and underscores, cannot start with AWS_, and the whole block is capped at 4 KB. Hand-building that JSON, or composing the --environment argument for the AWS CLI, from an existing .env is fiddly and easy to get subtly wrong.

The .env to AWS Lambda Converter produces the exact artifact you need. Choose raw JSON for the console/SDK/IaC, a CLI-ready key=value,key2=value2 string for aws lambda update-function-configuration, or a serverless.yml environment block for the deployment frameworks. Values are validated as strings, keys are checked against Lambda's rules, duplicates are reported, and the output size is measured against that 4 KB budget.

Both processes and infrastructure benefit from a deterministic, reviewable conversion that never leaves the browser — and never leaks a secret to a server.

• Three output modes: raw JSON, CLI argument string, or serverless.yml block.
• Key validation: letters, digits and underscore only; AWS_ prefix rejected.
• Duplicate detection: repeated keys are flagged with line numbers.
• 4KB budget check: the stats line shows the combined encoded size.
• Correct JSON: quotes and escapes handled so the block parses everywhere.
• Parameter Store option: route sensitive suffixes to {{resolve:ssm:...}} references.
• Copy or download: clipboard or a .json/.txt/.yml file in one click.
• Private: all conversion happens in your browser.

1. Paste your .env content into the input box, or load the sample.
2. Pick an output format — JSON, CLI, or serverless.yml.
3. Optionally enable Parameter Store references for secret-suffixed keys.
4. Click Convert. The Lambda environment block appears on the right.
5. Review warnings and the size stat, then copy or download.

Example 1 — SDK/console update. A backend engineer converts their .env to JSON and pastes it into Environment in the Lambda console, or passes it to the SDK update call.

Example 2 — AWS CLI. A DevOps engineer emits the CLI string and runs aws lambda update-function-configuration --function-name api --environment for a no-mistake deploy.

Example 3 — Serverless Framework. A serverless user drops the generated block into their serverless.yml provider.environment section and redeploys.

Example 4 — Secret routing. A security-minded team enables Parameter Store mode so API_KEY_SECRET arrives as a resolve reference instead of a plain value.

Example 5 — Multi-function consistency. A platform team regenerates identical environment blocks for regional replias, keeping configuration in sync everywhere.

• Always-valid blocks: Lambda rules enforced automatically.
• Three ready formats: pick JSON, CLI or serverless.yml.
• Budget-aware: size is measured against the 4KB limit.
• Deterministic: same input, same output, easy to review.
• Secret-aware: optional SSM references for sensitive keys.
• Private & free: browser-only conversion, no account.