CONSTANT_CASE Converter
Convert text to CONSTANT_CASE used for constants and environment variables.
What is CONSTANT_CASE?
CONSTANT_CASE (also called SCREAMING_SNAKE_CASE or MACRO_CASE) writes all letters in uppercase separated by underscores. It is the universal convention for constants and environment variables across nearly every programming language.
hello world example→HELLO_WORLD_EXAMPLEWhen to Use CONSTANT_CASE
Use CONSTANT_CASE for values that never change at runtime: environment variables (DATABASE_URL, API_KEY), global constants (MAX_RETRY_COUNT), enum values, configuration flags, and C/C++ macros.
Do not use CONSTANT_CASE for variables that change at runtime, function names, class names, or regular object properties. Its visual weight signals "this never changes" — overusing it creates confusion.
Industry Standard
CONSTANT_CASE is specified in the Google Java Style Guide, PEP 8 (Python), and the GNU Coding Standards for constants and macros. The POSIX standard uses CONSTANT_CASE for all environment variable names (PATH, HOME, USER, DATABASE_URL).
How to Use This CONSTANT_CASE Converter
- Paste or type your text into the Input Text box on the left.
- The output is converted to CONSTANT_CASE instantly on the right.
- Click Copy to copy the result to your clipboard.
- Use Clear to reset and convert new text.
CONSTANT_CASE in Programming Languages
const MAX_RETRIES = 3;MAX_RETRIES = 3static final int MAX_RETRIES = 3;#define MAX_RETRIES 3DATABASE_URL=postgres://localhost/mydbFrequently Asked Questions
Is this CONSTANT_CASE converter free?
Yes, completely free — no signup, no account, no limits.
Does my text get stored or sent anywhere?
No. All conversions happen entirely in your browser using JavaScript. Your text never leaves your device and is never sent to any server.
When should I use CONSTANT_CASE?
Use CONSTANT_CASE for values that never change at runtime: environment variables (DATABASE_URL, API_KEY), global constants (MAX_RETRY_COUNT), enum values, configuration flags, and C/C++ macros.
Expert tip
In .env files, ALL keys must be CONSTANT_CASE. Tools like dotenv (Node.js) and python-decouple expect this format. Never commit .env files to version control — add them to .gitignore and use CONSTANT_CASE keys in your documentation.