Case converter: title, sentence, upper and lower case

Convert text to title case, sentence case, UPPER or lower case, or to camelCase, snake_case and kebab-case, with character and word counts.

업데이트 검증한 예제: 6

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Title Case
The Quick Brown Fox Jumps Over the Lazy Dog
Title Case: The Quick Brown Fox Jumps Over the Lazy Dog
UPPER CASE
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
lower case
the quick brown fox jumps over the lazy dog
Sentence case
The quick brown fox jumps over the lazy dog
camelCase
theQuickBrownFoxJumpsOverTheLazyDog
snake_case
the_quick_brown_fox_jumps_over_the_lazy_dog
kebab-case
the-quick-brown-fox-jumps-over-the-lazy-dog
Characters
43
Words
9

43 characters in 9 words: 0 uppercase and 35 lowercase letters, 0 digits, 8 spaces and 0 other characters.

Characters by type

Uppercase0Lowercase35Digits0Spaces8Punctuation and symbols0
계산 방법 S
  1. Title Case

    Every word is capitalized except articles, conjunctions and prepositions of three letters or fewer (a, an, the, and, but, for, of, on, to…), which stay lowercase unless they are the first or last word or follow a colon (AP style). Existing capitals are lowered first, so acronyms need fixing by hand.

  2. Sentence case

    Everything is lowercased, then the first letter of each sentence and the pronoun “I” are capitalized. Proper nouns can't be detected.

  3. Identifier cases

    Split into 9 words (the, quick, brown, fox, jumps, over, the, lazy, dog) at spaces, punctuation and lower-to-upper case changes; apostrophes are dropped.

Case converter: title, sentence, upper and lower case 소개

The converter rewrites text in seven cases at once. Upper and lower case follow the Unicode default case mappings, so ß becomes SS. Title case capitalizes every word except articles, conjunctions and prepositions of three letters or fewer, which stay lowercase unless they come first, last or after a colon (AP style). Sentence case lowercases everything, then capitalizes the first letter of each sentence and the pronoun I. camelCase, snake_case and kebab-case split the text into words at spaces, punctuation and lower-to-upper changes, and drop apostrophes.

People use it to fix headings typed in capitals, format titles and turn phrases into variable names. The default, "the quick brown fox jumps over the lazy dog", becomes "The Quick Brown Fox Jumps Over the Lazy Dog" in title case and the_quick_brown_fox_jumps_over_the_lazy_dog in snake_case; it has 43 characters and 9 words.

Title and sentence case lower existing capitals first, so acronyms such as NASA and proper nouns need fixing by hand.

계산 예제

Pangram

텍스트
the quick brown fox jumps over the lazy dog
Show first
Title Case
Title Case
The Quick Brown Fox Jumps Over the Lazy Dog
UPPER CASE
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
camelCase
theQuickBrownFoxJumpsOverTheLazyDog
snake_case
the_quick_brown_fox_jumps_over_the_lazy_dog
kebab-case
the-quick-brown-fox-jumps-over-the-lazy-dog
Characters
43
Words
9

검증 출처: Python 3.8 str.upper and an independent re-based implementation of the AP title rule

Title with a colon

텍스트
the lord of the rings: the return of the king
Show first
Title Case
Title Case
The Lord of the Rings: The Return of the King

검증 출처: AP rule: short function words stay lowercase except first, last and after a colon (Python check)

Sentence case with a lone i

텍스트
HELLO WORLD. how ARE you? i am fine
Show first
Sentence case
Sentence case
Hello world. How are you? I am fine

검증 출처: Python 3.8 re implementation: capitalize after . ! ? and the pronoun I

Acronym and camel humps

텍스트
XMLHttpRequest parser
Show first
snake_case
snake_case
xml_http_request_parser
camelCase
xmlHttpRequestParser
kebab-case
xml-http-request-parser

검증 출처: Python 3.8 re split at [a-z0-9][A-Z] and [A-Z]+[A-Z][a-z] boundaries

자주 묻는 질문

Which words are not capitalized in title case?

In AP style, articles (a, an, the) and conjunctions and prepositions of three letters or fewer (and, but, for, nor, or, so, yet, as, at, by, in, of, off, on, per, to, up, via) stay lowercase unless they are the first or last word or follow a colon. Words of four letters or more, such as "over" and "with", are capitalized. The Chicago Manual of Style differs: it lowercases prepositions of any length, such as "between".

What is the difference between title case and sentence case?

Title case capitalizes most words (How to Write a Good Title); sentence case capitalizes only the first word, proper nouns and the pronoun I (How to write a good title). APA Style uses sentence case for the titles of articles and books in reference lists and title case for headings and for titles mentioned in the text.

What are camelCase, snake_case and kebab-case?

They join words without spaces so a phrase can be used as a name in code. camelCase capitalizes each word after the first (xmlHttpRequestParser), snake_case joins lowercase words with underscores (xml_http_request_parser) and kebab-case with hyphens (xml-http-request-parser). Python's PEP 8 style guide uses snake_case for function and variable names; kebab-case appears in CSS property names such as background-color and in URLs.

Why does ß become SS in upper case?

The Unicode Standard's default full case mapping, listed in SpecialCasing.txt, maps the German sharp s (ß) to the two letters SS, so "straße" (6 characters) becomes "STRASSE" (7). A capital sharp s, ẞ, was added in Unicode 5.1 in 2008, but the default uppercase mapping still gives SS. The character count here is for the text you typed.

Does the character count include spaces?

Yes. Characters counts everything you typed, spaces and punctuation included, and the chart splits the total into uppercase and lowercase letters, digits, spaces and other characters. The default sentence has 43 characters: 35 lowercase letters and 8 spaces. Each Unicode code point counts once, so some emoji count as two. Words are runs of text between spaces that contain a letter or digit.

“Case converter: title, sentence, upper and lower case”의 정확도는 어느 정도인가요?

정확도는 입력값과 계산 방법의 가정에 따라 달라집니다. 십진 연산은 유효숫자 50자리를 사용하지만, 추정값·수치해석 방법·원본 데이터의 정밀도는 더 낮을 수 있습니다. 표시값을 반올림해도 이러한 한계는 사라지지 않습니다. 독립적인 출처의 풀이와 대조한 계산 예시: 6. 예를 들어 “Pangram”은 Python 3.8 str.upper and an independent re-based implementation of the AP title rule와 대조해 확인합니다.

이 계산 방법의 출처는 무엇인가요?

Unicode Standard §3.13 — Default case algorithms (full case mapping, e.g. ß → SS); AP Stylebook — Composition titles (capitalize words of four or more letters).

이 계산기 소개

출처

  1. Unicode Standard §3.13 — Default case algorithms (full case mapping, e.g. ß → SS)
  2. AP Stylebook — Composition titles (capitalize words of four or more letters)

출처와 대조하여 검증

이 계산기에는 독립적인 출처에서 답을 얻은 계산 예제가 6개 있습니다. 테스트 모음에서 실행되며 여기에서도 실행할 수 있습니다.

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