大文字・小文字・ケース変換ツール
大文字、小文字、Title Case、camelCase、kebab-case等へワンクリック変換。
Text Case Styles Comparison
| Case Style | Example Output | Primary Application |
|---|---|---|
| Sentence case | The quick brown fox jumps over the lazy dog. | Standard body paragraphs, novels, articles |
| Title Case | The Quick Brown Fox Jumps Over the Lazy Dog | Article headlines, book titles, email subjects |
| Capitalized Case | The Quick Brown Fox Jumps Over The Lazy Dog | Tabular headers, badge captions, certificates |
| UPPERCASE | THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG | Acronyms, legal disclaimers, urgent alerts |
| lowercase | the quick brown fox jumps over the lazy dog | Clean data normalization, email addresses |
| kebab-case | the-quick-brown-fox-jumps-over-the-lazy-dog | SEO URL slugs, CSS class names |
| snake_case | the_quick_brown_fox_jumps_over_the_lazy_dog | Database table columns, Python variables |
Key Capabilities of 英字大文字・小文字変換
10+ Case Transformations
Instant one-click conversions for UPPERCASE, lowercase, Title Case, Sentence case, Capitalized, alternating, inverse, and kebab-case.
Text Whitespace Cleaner
Remove duplicate spaces, eliminate empty line breaks, and trim leading/trailing whitespace.
Live Character & Word Counts
Always know the exact character and word count of your converted text in real time.
One-Click Copy & Download
Instantly copy the converted result to your clipboard or download it as a plain .txt file.
文字数カウントに関するFAQ
How does Title Case capitalization work?
Our Title Case converter adheres to standard AP and Chicago editorial rules: it capitalizes the first and last words, all major nouns, verbs, adjectives, and adverbs, while keeping short conjunctions, prepositions, and articles (like "a", "an", "the", "in", "on", "of", "and") in lowercase.
What is Sentence Case?
Sentence case capitalizes only the first letter of each sentence and proper nouns, leaving all subsequent words in lowercase, mirroring standard grammatical prose.
What is Alternating Case (aLtErNaTiNg CaSe)?
Alternating case alternates between lowercase and uppercase characters (e.g. "hElLo WoRlD"), popularized in internet culture, memes, and social commentary.
Can this tool remove extra spaces and blank lines?
Yes. Use the "Remove Extra Spaces" button to collapse multiple consecutive spaces into a single space, or "Remove Empty Lines" to clean up messy formatting from pasted documents.
Is my text safe and private when converting case?
Yes, 100%. All string transformations execute directly inside your browser window. No text is ever uploaded, saved, or sent across any network.
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