This online JSON to .env converter transforms JSON configuration objects into environment variable files with flattened keys and proper value quoting.
Quickly convert JSON to environment variables, Docker Compose YAML and Kubernetes ConfigMaps in your browser with no server upload.
JSON to .env conversion is the process of transforming a structured JSON configuration object into a flat list of environment variables in the KEY=value format used by .env files, Docker, Docker Compose, Kubernetes ConfigMaps and most modern application frameworks. Nested keys are flattened using a separator so that hierarchical configuration becomes a single, deployable environment file.
Applications built on the Twelve-Factor methodology expect configuration to be provided through environment variables rather than hard-coded files. Converting JSON to .env lets you keep a single readable JSON source of truth in your repo or secret manager, while generating deployment-ready environment files for local development, Docker containers, CI/CD runners and cloud providers without rewriting values by hand.
Using this JSON to .env converter is simple:
.env, Docker Compose YAML, Kubernetes ConfigMap or Azure App Settings).: or __) and a case style (preserve original or UPPER_SNAKE_CASE)..env / .yaml file.Conversion runs in real time as you type, so you can iterate on your JSON and instantly see the matching environment file.
Our converter is 100% client-side, free and ad-free. Unlike many online converters, it never uploads your JSON to a server, which matters because configuration objects often contain internal hostnames, tokens and API keys. You also get multiple output targets, configurable key flattening and instant copy/download in a single tool.
The tool recursively walks your JSON tree. For each leaf value it builds a key by joining every parent key with the chosen separator, so {"database":{"host":"localhost"}} becomes DATABASE__HOST=localhost or database:host=localhost depending on your settings. Keys can be kept in their original case or upper-cased to UPPER_SNAKE_CASE, which is the convention for POSIX environment variables.
String values are automatically wrapped in double quotes and escaped, numbers and booleans are emitted as plain literals, and arrays are serialized to a quoted JSON string so the resulting .env file is safe to source from a shell or load with dotenv.
.env, Docker Compose, Kubernetes ConfigMap and Azure App Settings JSON.: or __)..env / .yaml.This JSON to .env converter is used across modern development and DevOps workflows:
.env files and environment: blocks for containers..env files consumed by dotenv, Next.js, NestJS and Vite.kubectl.Yes. All conversion runs entirely in your browser using JavaScript - your JSON is never uploaded, logged or stored on our servers. This client-side architecture protects secrets that sometimes live in configuration objects (database URLs, API keys, internal hostnames) and also makes conversion instant, even for large JSON files.
That said, real production secrets should never live in a plain .env committed to source control. Use a dedicated secret manager (HashiCorp Vault, AWS Secrets Manager, Kubernetes Secrets, Azure Key Vault) and only convert to .env on-the-fly at deploy time.
DevTools is a free suite of privacy-first online developer utilities. Every tool is ad-free, requires no sign-up and processes data locally in your browser. The JSON to .env converter is part of a consistent set of JSON utilities, so you can move between formatting, querying and converting JSON without leaving the same design, theme and keyboard shortcuts.
Once your JSON is converted you can instantly copy the output to the clipboard or download it as a .env or .yaml file, ready to drop into your project root, Docker image or Kubernetes manifest directory.
The converter also integrates with the rest of the DevTools JSON suite - use it alongside the JSON Formatter & Validator, the JSON to XML converter, and the JSON Query Explorer for a complete JSON workflow.
Nested objects are flattened by joining each level of keys with the separator you pick (: or __). For example {"db":{"host":"localhost"}} becomes DB__HOST=localhost.
Arrays are serialized to a quoted JSON string on a single line, for example TAGS="[\"prod\",\"eu\"]". This keeps the .env file shell-safe and lets you parse the value back with JSON.parse at runtime.
Yes - the conversion runs fully in your browser and nothing is sent to our servers. For production workloads you should still keep real secrets in a dedicated secret manager rather than in a plain .env file committed to git.
Booleans and numbers are written as plain literals without quotes (for example DEBUG=false, PORT=5432), so they can be loaded directly by dotenv and parsed as strings in POSIX shells.
Yes. Switch the Output Format to YAML and pick a subformat: Docker, Compose, Kubernetes ConfigMap or Azure App Settings. The tool will emit a complete manifest you can drop into your deployment.
Yes. If your input is not valid JSON the converter will show an error toast and keep the last valid output, so you can fix the syntax and continue where you left off.
Completely free, no registration, no ads, no usage limits and no tracking. All processing happens locally in your browser.
To learn more about environment variables, .env files and secure configuration management, check out these external resources:
.env files into process.env. .env files and environment: blocks with Compose.