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Constant Case Converter – Convert Text to CONSTANT_CASE Instantly

The ConvertCasePro CONSTANT_CASE converter transforms any text — including camelCase, PascalCase, phrases with spaces, or hyphenated words — into proper CONSTANT_CASE. All letters become uppercase and word boundaries become underscores.

INPUT_BUFFER
CHARS: 0WORDS: 0LINES: 0
OUTPUT_BUFFER // CONSTANT_CASE
CHARS: 0WORDS: 0LINES: 0

What Is CONSTANT_CASE?

CONSTANT_CASE is a naming convention where all letters are uppercase and words are separated by underscores. It is the uppercase variant of snake_case. Examples: • Input: max retry count • Output: MAX_RETRY_COUNT • Input: databaseConnectionString • Output: DATABASE_CONNECTION_STRING Also known as SCREAMING_SNAKE_CASE or UPPER_SNAKE_CASE — the all-caps visual weight signals: this value is fixed and should not change.

Where CONSTANT_CASE Is Used

  • •Environment variables: DATABASE_URL, API_KEY, NODE_ENV, SECRET_KEY, PORT, REDIS_HOST. CONSTANT_CASE is the universal standard for environment variables across all platforms and languages.
  • •Python constants: PEP 8 mandates CONSTANT_CASE for module-level constants — MAX_CONNECTIONS = 100, DEFAULT_ENCODING = 'utf-8', SUPPORTED_FORMATS = ('json', 'csv').
  • •JavaScript/TypeScript constants: Module-level fixed values conventionally use CONSTANT_CASE — const MAX_UPLOAD_SIZE = 10 * 1024 * 1024, const API_BASE_URL = 'https://api.example.com'.
  • •Java static final fields: public static final int MAX_RETRY_COUNT = 3, public static final String DEFAULT_CHARSET = 'UTF-8'.
  • •C/C++ preprocessor macros: #define BUFFER_SIZE 4096, #define MAX_PATH_LENGTH 255.
  • •SQL keywords (different use): SELECT, FROM, WHERE, GROUP BY — SQL keywords are conventionally uppercase to distinguish them from table and column names.

How to Convert Text to CONSTANT_CASE

  • •Paste or type your text into the input box.
  • •Click the CONSTANT_CASE button.
  • •Your text is instantly converted — all letters become uppercase and word boundaries become underscores.
  • •Click Copy to copy to clipboard, or Download to save as a text file.
  • •Works with text that has spaces, hyphens, camelCase, PascalCase, or any other separator format.

Why CONSTANT_CASE Exists

The purpose of CONSTANT_CASE is intent communication — making constants visually distinct from variables at a glance. Without it: if (retries > maxRetries) — is maxRetries a parameter, a local variable, or a constant? With CONSTANT_CASE: if (retries > MAX_RETRIES) — immediately clear: MAX_RETRIES is a fixed value defined at a higher scope. This readability benefit is why CONSTANT_CASE spread to virtually every mainstream language despite rarely being enforced by compilers.

Frequently Asked Questions

What's the difference between CONSTANT_CASE and UPPERCASE?
UPPERCASE converts all letters to capitals with no other changes — 'hello world' becomes 'HELLO WORLD'. CONSTANT_CASE replaces spaces and other separators with underscores — 'hello world' becomes 'HELLO_WORLD'.
Can I convert camelCase to CONSTANT_CASE?
Yes. Paste maxRetryCount and click CONSTANT_CASE — you get MAX_RETRY_COUNT. The converter splits on camelCase word boundaries.
Why do environment variables use CONSTANT_CASE?
Environment variables have used CONSTANT_CASE by convention since early Unix. The all-caps format makes them visually distinct from shell variables and program code, signaling that these are external configuration values.
Is CONSTANT_CASE the same as SCREAMING_SNAKE_CASE?
Yes. CONSTANT_CASE, SCREAMING_SNAKE_CASE, and UPPER_SNAKE_CASE are all names for the same format: all uppercase letters with underscores separating words.

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