11 Types of Conversion Results Comparable from a Single Input
The case converter simultaneously generates 11 types of results from the string in the input field. The displayed formats are UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case, kebab-case, full-width, half-width, hiragana, and katakana.
Instead of automatically determining the original format and converting it to a single correct answer, it applies different rules to the same input and displays the results side-by-side.
This allows users to compare and choose the result that best suits their needs.
The conversion is applied immediately to the current string as you type, and the results are displayed on the cards. There is no operation to switch conversion modes.
For example, clicking the sample button enters a sentence, though note that the English sample does not contain actual kana characters.
In UPPERCASE, characters with uppercase equivalents are capitalized, while full-width, half-width, and kana conversions attempt to process their respective character ranges.
Each is an independent output, so it is not a continuous process like converting to full-width and then to katakana.
When the input is cleared, the result cards are hidden, allowing you to start over with a sample or new input. The clear button is disabled when the input is empty.
The result fields preserve line breaks, and long results can be scrolled within the card. However, this feature does not guarantee a maximum processing limit or a constant response time.
For long texts, all 11 format types are calculated simultaneously whenever the screen renders, which may take time to display depending on your device, browser engine, and text volume.
The advantage of this configuration is that you can compare formats on a single screen. Since cards are independent rather than a sequential pipeline, to apply multiple changes—like converting to uppercase and then trying snake_case—you must copy the uppercase result and paste it back as input.
Full-width and half-width conversions handle defined character sets such as ASCII alphanumerics, standard spaces, and standard katakana sequences like ｶﾞ to ガ without altering unmapped characters.
Rules for UPPERCASE, lowercase, Title Case, and Sentence case
UPPERCASE and lowercase apply the standard JavaScript uppercase and lowercase conversion to the entire input. Rather than using a proprietary table limited to alphabetic characters, characters with uppercase and lowercase equivalents in Unicode are converted according to the browser's JavaScript implementation.
Characters without a corresponding case relationship, such as Japanese kanji, hiragana, katakana, and numbers, are generally left as is.
There is no setting to select language-specific notation rules, nor is there a function to determine the correct spelling of proper nouns.
Title Case matches word tokens starting with Unicode letters or numbers, followed by subsequent letters, marks, or digits, while preserving whitespace and punctuation between matches.
Capitalization is strictly mechanical: it capitalizes the initial character of each matched word token and lowercases the remainder.
For example, hELLO 日本語 wORLD becomes Hello 日本語 World. It does not apply editorial title casing dictionaries to keep minor English prepositions or conjunctions in lowercase, nor does it retain internal casing for brand names or acronyms like iPhone, McDonald, or API.
Sentence case first lowercases the entire input text, and then capitalizes each Unicode letter that appears at the start of the string or immediately after terminal punctuation—including ASCII marks (.!?) and full-width Japanese marks (。！？) followed by zero or more whitespace characters.
As a mechanical character rule rather than linguistic syntactic segmentation, it does not distinguish sentence-ending periods from abbreviation dots, nor does it perform natural language grammar parsing or proper noun recognition.
This processing is not grammar analysis. It does not distinguish ellipses, quotation marks, line breaks, proper nouns, or abbreviations by meaning.
Even if a period is a decimal point or part of an abbreviation, it is treated under the same rules. Since it is not a feature that fixes only a portion while preserving the original capitalization information, be sure to proofread the output before using it in sentences containing formal names.
Word Splitting for camelCase, snake_case, and kebab-case
For the three identifier naming formats (camelCase, snake_case, and kebab-case), input text is split into word candidates using regular expressions.
Boundaries include hyphens, underscores, whitespace runs including tabs and line breaks, transitions from lowercase or digits to uppercase letters, and script transitions between ASCII and Japanese characters.
Identifier formatting preserves Unicode letters (category L) and numbers (category N) rather than restricting transformation solely to ASCII characters.
Characters outside these categories—including emojis, punctuation marks, symbols, whitespace, and combining marks—function strictly as word delimiters rather than being preserved as distinct output tokens.
For instance, in the input hello😀world.example, the emoji and period serve as token boundaries between words rather than being retained themselves, yielding the three word tokens hello, world, and example.
This cleanly formats the result into camelCase as helloWorldExample or snake_case as hello_world_example without carrying over the punctuation or emoji.
For snake_case and kebab-case, word boundaries are established by regex patterns detecting transitions from lowercase letters or digits to uppercase letters, ASCII acronym clusters preceding a capitalized word, and boundaries between ASCII and Japanese scripts.
Because the parser operates mechanically without an English dictionary, acronym boundaries without clear case cues cannot be inferred.
Because identifier formats preserve Unicode letters and numbers, Japanese characters are retained intact alongside Roman characters.
An input such as 日本語Text yields 日本語Text in camelCase and 日本語_text in snake_case. However, without a dictionary or semantic vocabulary model, all-caps acronym clusters like XMLHTTPRequest cannot infer XML HTTP Request beyond defined regex boundaries.
This splitting does not reference the meaning of the input or known abbreviations. There is no dictionary function to infer that XMLHTTPRequest consists of the three words XML, HTTP, and Request; it only uses boundaries determined by character sequences.
Independent outputs for PascalCase, CONSTANT_CASE, BEM, and file extension protection are not provided. Before pasting into your code, verify the identifier rules of your specific language or project.
Full-width/Half-width Conversion and Handling of Voiced/Semi-voiced Marks
For full-width conversion, the tool uses the audited core mapping table shared with the Japanese version. Printable ASCII characters from exclamation mark through tilde (0x21–0x7E) and ASCII spaces map directly to their full-width counterparts (0xFF01–0xFF5E and U+3000).
Half-width katakana sequences, including voiced sound marks such as ｶﾞ becoming ガ, ﾊﾟ becoming パ, and ｳﾞ becoming ヴ, are converted using standard NFKC normalization.
Kanji, hiragana, and emojis remain outside this finite character mapping.
For half-width conversion, full-width ASCII alphanumeric characters and full-width ideographic spaces (U+3000) map directly back to standard half-width ASCII.
Full-width katakana characters with half-width equivalents map to their corresponding single or two-character half-width forms (such as ガ to ｶﾞ).
Half-width ASCII characters remain unaffected and are not altered by the conversion.
The terms full-width and half-width refer strictly to character code point transformations rather than dynamic visual display measurement or global Unicode grapheme layout.
The conversion targets are bounded to the defined ASCII ranges (0x21–0x7E), ideographic space (U+3000), and defined katakana sets.
Characters lacking direct width counterparts in these finite tables—including kanji, hiragana, symbols, and emojis—remain untouched outside the conversion mapping.
The 11 format cards operate independently from the raw input rather than in a sequential transformation pipeline. While character conversions accurately map defined code points and voiced katakana marks, you should not treat purely mechanical conversion rules as a substitute for domain-specific schema normalization, database primary key sanitization, or linguistic text analysis where custom normalization rules are mandated.
Hiragana/Katakana Conversion and Copy Operation
Hiragana conversion shifts full-width katakana in the basic range (U+30A1 to U+30F6) to the corresponding basic hiragana. Katakana conversion shifts basic hiragana (U+3041 to U+3096) to full-width katakana.
This basic range conversion operates independently by shifting character codes by a difference of 0x60 (decimal 96). Characters outside the target range, such as middle dots, kanji, and alphanumeric characters, are left as is.
For example, converting カタカナ・漢字 results in かたかな・漢字, and ひらがな・漢字 results in ヒラガナ・漢字.
The hiragana and katakana conversion performs a direct character code offset shift between full-width hiragana (U+3041–U+3096) and full-width katakana (U+30A1–U+30F6).
It is purely a character-level exchange: it cannot infer kanji readings into furigana, convert romanized English spellings into Japanese kana, or evaluate phonetic okurigana context.
Because each card operates independently on the source input, half-width katakana must be converted to full-width first if hiragana output is desired.
Each result card includes a dedicated copy button. When pressed, the component requests clipboard write access and waits for the operation to resolve before displaying a success checkmark for two seconds, ensuring that visual confirmation only occurs after the text has actually been written.
If the browser denies clipboard permissions or does not support automated copying, an accessible alert message appears directly on screen.
Because all converted text is rendered in selectable result fields, you can highlight the text manually and copy it using standard keyboard shortcuts or your operating system's clipboard commands.
Unsupported Ranges and Handling of Input Data to Check in Practice
The conversion functions read the input string in the React state of this page and create new strings within the browser. No API transmission or database saving processes for conversion are implemented.
However, this does not mean that communication for page loading, site common functions, advertisements, or browser extensions does not exist.
Please judge whether to handle confidential information based on your device, browser, installed extensions, and clipboard handling.
All outputs are generated by deterministic character-level rules rather than semantic linguistic analysis. Title Case and Sentence case adhere to explicit punctuation and capitalization patterns, while naming formats preserve Unicode letters and numbers using punctuation and whitespace as word boundaries.
Width and kana tools operate strictly across documented ASCII and kana code ranges.
For example, there is no function to rewrite all keys of an API response at once or to safely refactor variable references in source code.
This screen handles a single pasted string and does not read syntax trees or file structures. Names used for programming must be checked separately for reserved words, duplication, and matching with references after conversion.
In practice, test your text with short representative examples to confirm that the expected token boundaries and script transitions are formed.
While identifier formats preserve Unicode letters and numbers across ASCII and Japanese characters, mechanical rules cannot infer dictionary-specific compound words or acronym groupings.
The 11 simultaneous result cards provide a rapid comparative reference for evaluating candidate formats before adoption.