A short field guide to text cases
Every developer, writer, and designer eventually needs to flip text between cases. The trick is knowing which case belongs where — and most "case converter" tools just dump every variant on you without context. Here's the actual map.
The thirteen cases this tool produces
UPPERCASE — every letter capitalized. Used for legal "shouting" (NOTICE, WARNING), brand wordmarks, acronyms (NASA, HTTP), and dramatic emphasis. Avoid in body copy because all-caps text is roughly 10–15% slower to read.
lowercase — no capitals at all. Quietly cool — popular in modern brand wordmarks, hashtags, and identifiers. Reads fast.
Title Case — every word capitalized. Standard for book and article titles ("How to Train Your Dragon"), section headings, and many marketing surfaces. The catch: real-world Title Case keeps short words (a, the, of, and, but) lowercase unless they start the title. Our converter does the simple version — every word capitalized — which is what most CMSes do too.
Sentence case — only the first word and proper nouns capitalized. The default for body copy and increasingly for UI labels and button text on modern apps. Apple, Google Material, and most design systems prefer Sentence case for everything except headings.
Programmer cases
camelCase — first word lowercase, every following word capitalized, no spaces. JavaScript and Java variables, JSON keys, function names. Born for languages where identifiers can't contain spaces or hyphens.
PascalCase — like camelCase but the first letter is also uppercase. Used for class names, type names, React components, and namespaces. The "MyClass" of the world.
snake_case — words separated by underscores, all lowercase. The Python and Ruby standard, and the SQL convention for column names (user_id, created_at). Easier to scan in long identifiers than camelCase.
kebab-case — words separated by hyphens, all lowercase. URLs (/blog/my-post), CSS class names (.btn-primary), npm package names, and HTML attribute values. Hyphens beat underscores here because URL conventions favor them.
CONSTANT_CASE — words separated by underscores, all uppercase. Reserved for constants and environment variables (API_KEY, MAX_RETRIES). Visually shouts "do not change this."
dot.case — words separated by periods. Configuration keys, namespaces, JS object paths.
path/case — words separated by slashes. File paths, route segments.
The fun ones
iNVERSE cASE — flip every letter's case. Mostly useful for catching subtle case-sensitivity bugs.
aLtErNaTiNg cAsE — alternate every other letter. SpongeBob memes. That's the only legitimate use.
Why a single conversion tool beats thirteen
Most online case converters give you UPPERCASE and lowercase, and that's it. Or they give you all the cases on separate pages, which means thirteen tabs to find the one you want. This tool runs every variant in parallel against the same input — paste once, scan the cards, copy the one that matches your target.
The conversion happens entirely in your browser. There's no signup, no rate limit, no daily quota, and your text never leaves the tab. Paste a confidential variable name, an internal class identifier, or a draft tweet — none of it touches a server.
A note on word boundaries
Every case in this tool needs to know where the words start and end. The tokenizer splits in two places: at any non-alphanumeric character (spaces, hyphens, dots, slashes, underscores) and at lowercase-to-uppercase transitions inside an identifier. So "myVariableName", "my-variable-name", "my_variable_name", and "my variable name" all produce the same word list — and any of those four can be converted to any other in one step.