Case converter

The case converter edits plain text in one input area. It changes capitalization and, for identifier modes, the separators between words. It does not rewrite wording, correct spelling, translate text, or judge whether a heading follows a particular publication's style guide. Select a word or passage before choosing a mode to change only that selection. If nothing is selected, the mode applies to the complete input.

Six buttons are available: title case, sentence case, upper case, lower case, camel case, and kebab case. Each button updates the text in place, so the next action uses the current version. Title and sentence modes keep spaces and punctuation. Upper and lower modes apply the browser's Unicode case conversion. Camel and kebab modes split the targeted text into letter and number tokens, discard punctuation and separators, then rebuild those tokens in a code-friendly form.

Title case first converts all input to lowercase, then capitalizes a letter at each word boundary. For example, SMALL steps FOR NASA becomes Small Steps For Nasa. That output is mechanically consistent, but it does not preserve the conventional uppercase form of NASA and it capitalizes short words such as for. Sentence case also starts from lowercase text. It capitalizes the first letter after the start of the string or after a period, exclamation mark, or question mark followed by whitespace. It is useful for regular prose, but it is not a grammar checker and cannot identify names that need internal capitals.

Upper case and lower case retain the existing spaces, line breaks, and punctuation while changing letters wherever the browser has a case mapping. Camel case tokenizes on any character that is not a Unicode letter or number. The first token becomes lowercase; every later token starts with an uppercase letter and continues in lowercase. Customer ID 42 becomes customerId42. Kebab case uses the same tokens, lowercases all of them, and joins them with hyphens, producing customer-id-42. Empty separators disappear, so repeated spaces, underscore characters, slashes, and punctuation do not create empty segments in either identifier mode.

Suppose a heading arrives as QUARTERLY SALES: NORTH AMERICA. Title case returns Quarterly Sales: North America, while sentence case returns Quarterly sales: north america. Neither result knows that North America is a proper name. A careful review would restore the capital A after conversion. If the same input is intended as a URL slug, kebab case returns quarterly-sales-north-america. The colon disappears because identifier modes treat punctuation as a separator. That is often desirable for slugs, but it means punctuation cannot be recovered from the result alone.

For a code-oriented example, convert user_profile.API-v2 with camel case. Tokenization produces user, profile, API, and v2. The result is userProfileApiV2, not userProfileAPIV2, because every token is normalized to lowercase before its first letter is adjusted. Kebab case returns user-profile-api-v2. If an existing identifier contains meaningful internal capitals, save the original and review the result manually. The converter aims for predictable normalization, not language-aware acronym preservation. This makes it useful for rough identifier preparation while leaving naming policy decisions to the developer.

Numbers pass through upper, lower, title, and sentence modes unchanged. In camel and kebab modes, numbers are tokens or parts of tokens depending on adjacent characters. version2 beta stays as two tokens and becomes version2Beta or version2-beta. Emoji and symbols stay in prose-oriented modes, but identifier modes remove them as separators. Line breaks remain in title, sentence, upper, and lower output. Camel and kebab modes collapse all lines into one identifier because their output is built from a single token list. Do not use those modes when line structure must survive.

The converter recognizes Unicode letters and numbers when it creates identifier tokens, so accented Latin letters and many non-Latin scripts are not discarded merely for being outside ASCII. Case behavior still depends on JavaScript and Unicode mappings available in the browser. It is not locale-selectable. Turkish dotted and dotless I, German sharp S, Greek final sigma, and similar language-specific cases deserve direct review. The tool also has no protected-word list. Brand casing such as iPhone, eBay, OpenAI, or PowerShell can be flattened and must be restored by the person preparing the final text.

Conversion runs in the page using JavaScript string methods and regular expressions. The editable text is held in the current browser session while you work. The transformation does not require a file upload or a server response. Reset clears the input from the workbench state, and leaving or reloading the page normally discards that state. You can select and copy the edited text with the browser's standard keyboard or context-menu controls.

Local processing reduces the need to send routine text to a conversion service, but it does not turn the browser into an approved environment for every type of information. Browser extensions, managed-device policies, clipboard history, screen recording, and other local software may still have access according to their permissions. Avoid pasting secrets, credentials, unpublished personal data, or regulated records unless your organization's rules permit that use. The tool does not store a conversion history, recover a reset value, or provide an audit log showing who converted a piece of text.

Capitalization rules vary by language, publisher, programming language, and project. The title mode does not implement AP, Chicago, sentence-style product copy, or any other editorial rule set. It does not lowercase articles selectively, recognize proper nouns, or protect acronyms. The sentence mode detects only a narrow punctuation pattern and does not understand quotations, abbreviations, decimal points, or sentence boundaries without whitespace. Treat both modes as deterministic text transformations. They reduce repetitive editing, but the output still needs an editor when capitalization affects meaning or house style.

Camel and kebab output are candidate identifiers, not validation for a target system. Some languages prohibit identifiers that begin with a number, reserve certain names, distinguish ASCII from Unicode, or impose a length limit. A kebab string may be suitable for a web slug yet unsuitable for a JavaScript variable, while camel case may be legal in one API and rejected by another. The converter does not test uniqueness, reserved words, URL routing, filesystem restrictions, or database naming rules. Validate the result where it will actually be used before replacing an existing identifier.

If title or sentence output loses expected capitals, check whether the source contains an acronym, brand, personal name, or place name. Those modes intentionally lowercase the source before capitalizing selected positions, so the lost casing cannot be inferred afterward. Restore the required spelling in the result or choose upper or lower mode when uniform casing is the actual goal. If sentence case fails to capitalize after punctuation, look for a missing whitespace character. Its rule expects a period, question mark, or exclamation mark followed by whitespace before the next letter.

If camel or kebab output joins or separates text unexpectedly, inspect the characters between the words. Any run of non-letter and non-number characters becomes a boundary, including underscore characters, apostrophes, emoji, and punctuation. Existing camelCase text with no separator is treated as one token and becomes camelcase in both identifier modes. Insert spaces before internal capitals if you need them recognized as separate words. To copy the edited value, select the required text and use the browser's standard copy command.

Review in two passes. First compare meaning-bearing details: acronyms, names, numbers, punctuation, line breaks, and words with internal capitals. Then check the destination's rules, such as a heading style, variable naming convention, route format, or import requirement. For prose, read at least the first sentence of every paragraph because sentence capitalization after abbreviations may need repair. For identifiers, test the result in the compiler, router, form, or content system that will consume it. Keep the source until that check succeeds, since identifier modes intentionally remove separator information.

Use Word counter when the question is word or character length rather than capitalization. It also reports sentences, paragraphs, and estimated reading time. Remove duplicate lines is designed for repeated list entries and does not change case before comparison. URL encode prepares text as one URL component; kebab case merely creates a hyphenated identifier and does not percent-encode reserved characters. HTML escape changes markup-sensitive characters into entities. Each tool solves a different representation problem, so converting case should be one deliberate step rather than a substitute for validation or encoding.

For a batch of headings or identifiers, write down the chosen mode and the exceptions that must be restored afterward. A content team might use sentence case, then restore a list of approved product names. A development team might use kebab case, then run the result through route validation. This page processes one pasted string at a time and has no saved preset, exception dictionary, or batch report. A short written rule prevents different reviewers from choosing modes based only on how one sample looks.

Keep a representative test set containing punctuation, an acronym, a number, an accented word, a line break, and an existing identifier. Run that set again if the destination's naming policy changes. Expected outputs expose differences between mechanical conversion and editorial preference. They also make it clear when a later manual correction is required. The converter supplies consistent character rules; reproducibility comes from pairing those rules with recorded examples and a review checklist owned by the project.