Case Converter

Instant offline case conversions. Everything processed locally on your client.

Central Input Sandbox

Characters: 55Words: 8

All Casing Outcomes (Click to Copy)

Understanding Developer Casing Conventions

Case conversion tools are vital for developers working across diverse languages and syntax protocols. Here is a brief guide to the standard case formats supported by ZeroServer:

Case Formats Defined

camelCase: The first word starts lowercase, and subsequent words are capitalized with no spaces. Standard in JavaScript/TypeScript variable names and API payloads.
snake_case: All words are lowercased and joined with underscores. The dominant standard in Python variables, database column names, and PostgreSQL keys.
kebab-case: All words are lowercased and joined with hyphens. The standard convention for URLs, slug generation, and CSS class names.
CONSTANT_CASE: All words are uppercased and joined with underscores. Used widely for environment variables, global configurations, and constants in Java, C, and JavaScript.

Built and maintained by Meet Shah · Last updated 5 August 2026

What this tool is used for

Converting a heading to title case consistently rather than by eye.
Turning a label into camelCase or snake_case for a code identifier.
Normalising a column of inconsistently cased values.
Converting a shouted paragraph back into sentence case.
Producing a constant name from a human-readable label.

How it works in practice

A worked example

A camelCase field name has to become a database column, and a book title in the same paste has to become a heading.

Input

helloWorld café — a tale of two cities

Output

SNAKE_CASE     hello_world_café_a_tale_of_two_cities
KEBAB-CASE     hello-world-café-a-tale-of-two-cities
CAMELCASE      helloWorldCaféATaleOfTwoCities
CONSTANT_CASE  HELLO_WORLD_CAFÉ_A_TALE_OF_TWO_CITIES
TITLE CASE     Helloworld Café — a Tale of Two Cities

Two things in that output are harder than they look. The camel boundary in the first word was seen, so it became two words rather than one run of letters — a converter that splits on spaces alone returns helloworld and quietly loses the distinction the name was carrying. And the accented character survived: an implementation that strips anything outside the plain Latin alphabet turns café into caf, which is not a conversion but a deletion. The last row keeps of lowercase, because title case is an editorial convention rather than a capitalisation of every word.

The edge case that catches people

That title-case row is the one that surprises people, and both halves of it are deliberate. Articles, coordinating conjunctions and short prepositions stay lowercase unless they lead or end the line, which is why a tale of two cities keeps its of — the alternative, capitalising every word, is what most naive implementations do and it reads wrong to anyone who has edited copy. And the camel word came back as Helloworld rather than HelloWorld, because title case is for prose: it lowercases what it does not recognise as a sentence boundary.

When not to use this tool

Not on anything where the casing is load-bearing. An identifier that already means something in its own language — a constant, an acronym inside a name, a filename on a case-sensitive filesystem — can be changed into a different identifier by a conversion that is perfectly correct as English. The same applies in bulk: converting a column of mixed values will make some of them right and some of them wrong, and there is no way to tell which from the output alone. Convert one thing you can read, or convert with a rule you wrote yourself.

Frequently Asked Questions

What is camelCase?: camelCase runs words together with each subsequent word starting with a capital: myVariableName. It's the standard convention in JavaScript and Java for variable/function names and in JSON for keys.
When should I use snake_case vs camelCase?: snake_case is standard in Python, Ruby, SQL column names, and shell scripts. camelCase is standard in JavaScript, Java, and C#. kebab-case is used for CSS class names and URL slugs. Match the convention for your language.
What is SCREAMING_SNAKE_CASE?: All uppercase letters with underscores: MY_CONSTANT. It's the universal convention for constants and environment variables in Python, JavaScript, Java, C/C++, and most other languages.
How are acronyms handled in conversion?: Acronyms (URL, API, HTML) are treated as single tokens. 'parseHTML' converts to 'parse_html' in snake_case. Some style guides prefer 'parse_HTML' — review the output and adjust if your convention differs.
Can I convert multiple identifiers at once?: Yes. The converter processes all text in the input, converting each identifier-like token separated by common delimiters (spaces, underscores, hyphens, and camelCase word boundaries).

Common errors and gotchas

Applying title case mechanically, which capitalises articles and prepositions that should stay lower.
Converting an acronym to sentence case, which turns HTTP into Http.
Losing intentional casing in a proper noun or a brand name.
Assuming a locale-independent lowercase, where Turkish dotted and dotless i behave differently.
Converting a value that is compared case-sensitively somewhere downstream.