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Writing & Utility

Case Converter

A case converter takes one block of text and instantly generates it in every common capitalization style, including UPPER CASE, lower case, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE. Type or paste your text into the box, click Convert Case, and the tool reads each word boundary in your input, whether it is marked by a space, a _ character, a hyphen, or an internal capital letter, then rebuilds the phrase using the capitalization and separator rules of every supported format at once. Writers use it to fix text pasted from a spreadsheet that landed in all caps, developers use it to turn a plain phrase into a valid variable name, and editors use it to standardize headline capitalization across a batch of articles. Everything runs in your browser, so nothing you type is uploaded or stored anywhere.

Writing & UtilityBy

Quick answer

Converts text to upper, lower, title, sentence, camel, pascal, snake, kebab, and constant case in a single pass.

What this tells you

  • Converts text to upper, lower, title, sentence, camel, pascal, snake, kebab, and constant case in a single pass.
  • Word normalization splits your input on spaces, _ characters, hyphens, and camelCase boundaries before rebuilding each format.
  • Title Case and Pascal Case capitalize the first letter of every detected word and lowercase the rest.
  • camelCase keeps the first word lowercase and capitalizes every word after it, with no separators between words.
  • snake_case, kebab-case, and CONSTANT_CASE join words with a _ character, a hyphen, or uppercase words joined by _ instead of spaces.
  • Outputs update instantly and are generated entirely client-side from the text you provide, so nothing leaves your browser.

How to Use

  1. 1Paste or type the text you want to convert into the input box. Full sentences, short phrases, and single words all work.
  2. 2Click Convert Case to generate every supported case format from that one input.
  3. 3Scan the results panel for the format you need, such as camelCase for a JavaScript variable or Title Case for a headline.
  4. 4Copy the output format you need directly from the results, ready to paste into your code editor, CMS, or document.
  5. 5If your source text already mixes styles, such as a snake_case variable name you want turned into a readable title, run it through once and confirm the split points match what you expect before using the result.

How It Works

Formula

Word normalization -> case-specific transformations (capitalization + separators)

The tool first tokenizes your text into individual words. It inserts a space before every lowercase-to-uppercase transition (so 'helloWorld' becomes 'hello World'), then treats _ characters and hyphens as word breaks and collapses everything into a clean list of lowercase words. From that shared word list, each output format applies its own two rules: a capitalization rule (leave lowercase, capitalize first letter, or uppercase everything) and a separator rule (space, no separator, _ character, hyphen, or _ character with uppercase). Upper case and lower case skip tokenization entirely and just change every character in the original string. Sentence case lowercases the whole string, then capitalizes the first letter of the string and the first letter after any period, question mark, or exclamation point followed by whitespace.

Calculation note: values are processed in the order shown above, using the current input units.

Worked Examples

Convert a phrase to programming and writing cases

Texthello world test
ResultcamelCase: helloWorldTest, snake_case: hello_world_test, Title Case: Hello World Test

The tool splits the phrase into three words (hello, world, test) using the spaces as boundaries. camelCase keeps the first word lowercase and capitalizes the rest with no separators, snake_case joins all three lowercase words with _ characters, and Title Case capitalizes the first letter of each word while keeping the spaces.

Normalize a snake_case variable name into a readable title

Textuser_first_name
ResultTitle Case: User First Name, PascalCase: UserFirstName, kebab-case: user-first-name

The _ characters in user_first_name are detected as word boundaries, so the tool splits it into user, first, and name before rebuilding each format. Title Case turns it into a readable label for a form or report, while PascalCase produces a class-name-style identifier and kebab-case produces a URL-friendly slug.

Convert a camelCase identifier into CONSTANT_CASE

TextmaxRetryCount
ResultCONSTANT_CASE: MAX_RETRY_COUNT, snake_case: max_retry_count, Title Case: Max Retry Count

Because maxRetryCount has no spaces, the tool detects word breaks at each lowercase-to-uppercase transition, splitting it into max, retry, and count. CONSTANT_CASE uppercases every word and joins them with _ characters, which matches the naming convention many languages use for constant values.

Clean up text pasted from an all-caps spreadsheet cell

TextTOTAL REVENUE Q3
ResultTitle Case: Total Revenue Q3, sentence case: Total revenue q3, lower case: total revenue q3

Spreadsheet exports and legacy databases often store labels in all caps. Title Case restores each word's capital first letter for a report heading, while lower case gives a clean, fully lowercase version useful for search matching or slug generation before further edits.

Turn a sentence into a kebab-case URL slug

TextBest Budget Laptops 2026
Resultkebab-case: best-budget-laptops-2026, snake_case: best_budget_laptops_2026

The tool splits the sentence into words on the spaces (Best, Budget, Laptops, 2026), lowercases each one, and joins them with hyphens for kebab-case or _ characters for snake_case. Kebab-case is the format most CMS platforms and web frameworks expect for URL slugs.

Common mistakes

  • Assuming the converter recognizes acronyms and proper nouns. Words like 'USA', 'NASA', or 'McDonald's get flattened into the target case rules just like any other word, so you often need to fix a handful of characters by hand after converting.
  • Running mixed-format text through the tool without checking the split points. Text that already combines camelCase and snake_case, such as 'userID_value', can split in a way you did not expect, so it is worth scanning the tokenized result before copying it into code.
  • Using Sentence case on text full of abbreviations. Periods after abbreviations like 'e.g.' or 'Inc.' are indistinguishable from real sentence endings to the tool, so the word right after an abbreviation can get an unwanted capital letter.
  • Pasting code snippets that include punctuation, symbols, or multiple identifiers at once. The tool tokenizes on spaces, hyphens, _ characters, and camelCase boundaries, not on commas, parentheses, or semicolons, so converting a full line of code usually produces messier results than converting one identifier at a time.
  • Forgetting that upper case and lower case do not use word tokenization at all. They change every character in your original string directly, so any typos, extra spaces, or inconsistent spacing in your input carry straight through to the output.

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Frequently Asked Questions

It changes capitalization style and word separators to generate common programming and writing case formats from the same input text. The underlying words and their order stay the same, only how they are capitalized and joined changes.
Yes. It generates camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE alongside upper case, lower case, Title Case, and Sentence case, all from one input.
Yes. Automatic conversion is useful for the bulk of the work, but it cannot detect proper nouns, acronyms, or brand names, so a quick manual check catches cases like 'iPhone' or 'NASA' that need to keep their original capitalization.
The tool treats every detected word the same way and applies the target format's capitalization rule to it, so it cannot tell that 'API' or 'NASA' should stay uppercase. Fix acronyms manually after conversion, or convert the rest of the phrase and re-add the acronym separately.
camelCase lowercases the first word and capitalizes every word after it with no separators, producing results like 'firstName'. PascalCase capitalizes every word including the first one, producing results like 'FirstName', which is the convention most languages use for class and type names.
Sentence case looks for a period, question mark, or exclamation point followed by whitespace to decide where a new sentence starts. Abbreviations like 'e.g.' or 'Dr.' contain a period followed by a space, so the word right after them can get capitalized even though no new sentence actually began.
Yes. kebab-case produces lowercase, hyphen-separated text that matches the slug format most content management systems and web frameworks expect for URLs, such as turning 'Best Budget Laptops 2026' into 'best-budget-laptops-2026'.
No. All tokenization and case transformation happen directly in your browser using the text you enter, and nothing is sent to a server or saved after you leave the page.
The tool treats every _ character and hyphen as a word boundary, along with every lowercase-to-uppercase transition. If your original text mixes styles, such as 'user_ID_value', the _ character and the capital letters both count as breaks, which can produce more or fewer words than you expected.
No. Both join words with a _ character, but CONSTANT_CASE uppercases every letter, producing results like 'MAX_RETRY_COUNT', while snake_case keeps every letter lowercase, producing results like 'max_retry_count'. CONSTANT_CASE is the common convention for constants and environment variables.
It estimates case converter outputs using the visible inputs and formula assumptions on this page.

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