What is SCREAMING_SNAKE_CASE?

SCREAMING_SNAKE_CASE writes a name in all uppercase with underscores between words, like MAX_RETRY_COUNT. It is the near-universal convention for constants in code and for environment variable names in shells and config files.

When should I use it?

Use it for compile-time or runtime constants, enum members in some languages, preprocessor macros in C, and environment variables such as DATABASE_URL or API_BASE_URL. The uppercase signals that the value should not change.

How does it handle camelCase input?

It detects the lowercase-to-uppercase boundaries inside camelCase and PascalCase strings, splits at those points, then uppercases everything and joins with underscores. So maxRetryCount becomes MAX_RETRY_COUNT.

Are environment variable names case sensitive?

On Unix-like systems environment variable names are case sensitive, and the strong convention is all uppercase. Sticking to SCREAMING_SNAKE_CASE avoids subtle bugs where MyVar and MYVAR are treated as different variables.

Is my input uploaded?

No. Everything runs in your browser. Your text is never sent to a server or stored anywhere.

SCREAMING_SNAKE_CASE Converter

SCREAMING_SNAKE_CASE — all uppercase with underscores — is the standard way to name constants in code and environment variables in shells and config files. This converter rewrites any phrase or identifier into that format.

How it works

The input is split into a list of word tokens, each token is uppercased, and the tokens are joined with underscores. Boundaries come from separators and from case transitions in camelCase or PascalCase input:

"max retry count" -> MAX_RETRY_COUNT
"maxRetryCount"   -> MAX_RETRY_COUNT
"max-retry-count" -> MAX_RETRY_COUNT
"databaseUrl"     -> DATABASE_URL

Every detected word is uppercased before joining, so the result is always a valid, uppercase, underscore-separated constant name.

Tips and notes

This format clearly signals immutability, which is why it is reserved for constants and configuration. On Unix-like systems environment variable names are case sensitive, so keeping them uppercase avoids collisions between names that differ only in case. Letters and digits are separated during tokenisation; rejoin a segment like a version number after copying if you prefer it attached.