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Text Case Converter

Convert text to UPPERCASE, lowercase, Title Case, Sentence case, Alternating case, or Reverse Text instantly. Also generates camelCase, PascalCase, snake_case, kebab-case, dot.case, and CONSTANT_CASE for developers — free, live, and private.

6 case modes 6 dev formats 100% client-side Updated: Jul 19, 2026
🔒 Your text never leaves this page — all conversion happens on your device, in your browser.
Selected format: UPPERCASE
Words 0 Characters 0 No spaces 0 Lines 0 Sentences 0
Quick answer To convert text case, paste your text above and pick a mode: UPPERCASE, lowercase, Title Case, Sentence case, Alternating case, or Reverse Text. Title Case capitalizes each main word while keeping short words like "a", "the", and "of" lowercase in the middle of a title. The tool also generates developer formats — camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE — from the same text, entirely in your browser.
6Case modes (UPPERCASE → Reverse)
6Developer formats (camelCase, etc.)
Aa → aAInstant live preview
0Data sent to a server
🔒 Privacy: Everything you type is processed locally in your browser — nothing is uploaded or stored on a server. Text is only encoded into the page URL if you click Share or Copy link (very long text is trimmed).
🔤 Text Case Converter — ToolPico ↗

What is a text case converter, and how does it work?

A complete guide to UPPERCASE/lowercase conversion, Title Case rules, Sentence case, Alternating case, Reverse Text, and developer naming formats.

A text case converter rewrites the letters of a text according to a rule you pick, without changing the words themselves. It's used to fix text that was accidentally typed in ALL CAPS, format a heading correctly, punctuate a paragraph into proper sentences, or generate a code-friendly variable name. The tool above handles all of these in separate tabs, instantly, entirely in your browser.

How do I convert text to UPPERCASE or lowercase?

Quick answerClick the UPPERCASE tab to convert every letter to a capital letter, or the lowercase tab to convert everything to small letters. Both use the browser's standard case-conversion rules and update instantly as you type — useful for fixing text typed with Caps Lock stuck on, or for normalizing text before storing it.

What is Title Case, and which words stay lowercase?

Quick answerTitle Case capitalizes the first letter of each main word in a title. This tool keeps short "minor" words — articles, conjunctions, and short prepositions like a, an, the, and, or, of, in, to, with — lowercase when they fall in the middle of a title, while the first and last word are always capitalized. So "the quick fox and the lazy dog" becomes "The Quick Fox and the Lazy Dog", not every single word capitalized.

Tools that skip this rule capitalize every word, producing an unnatural-looking title like "The Quick Fox And The Lazy Dog." Following standard style-guide conventions for minor words makes headlines and titles read correctly.

What is Sentence case, and how is it different from Title Case?

Quick answerSentence case capitalizes only the first letter of each sentence and lowercases the rest — ideal for turning a shouted or randomly-cased paragraph into normal prose. Title Case capitalizes the first letter of each main word instead — used for headlines, product names, and menu items. Use Sentence case for body text, Title Case for titles.

What are Alternating Case and Reverse Text used for?

Quick answerAlternating Case (also called "sPongeBob case") switches each letter between lowercase and uppercase in sequence, mostly used for humor or emphasis on social media. Reverse Text flips the entire string back to front, letter by letter — handy for novelty messages, simple obfuscation, or checking whether a phrase reads the same backward. Neither changes the meaning of the text, only its appearance.

When should I use camelCase, snake_case, or other developer formats?

Quick answerThese are naming conventions used across programming languages: camelCase (JavaScript/Java variables), PascalCase (class/component names), snake_case (Python and database columns), kebab-case (URL slugs and CSS classes), dot.case (config keys and npm namespaces), and CONSTANT_CASE (environment variables and constants). The Developer formats section below generates all six automatically from the same text.

Example conversions (all modes)

Every case mode applied to the same sample sentence.

Input → Output, by mode
ModeOutput
Inputthe quick fox and the lazy dog
UPPERCASETHE QUICK FOX AND THE LAZY DOG
lowercasethe quick fox and the lazy dog
Title CaseThe Quick Fox and the Lazy Dog
Sentence caseThe quick fox and the lazy dog
aLtErNaTiNg cAsEtHe QuIcK fOx AnD tHe LaZy DoG
Reverse Textgod yzal eht dna xof kciuq eht

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Developer formats: camelCase, snake_case, and more

The text above is automatically converted into 6 common programming naming conventions, plus an inverted-case variant — each with its own copy button.

🐫camelCase
JavaScript, Java, and Swift variable naming standard.
—
🅿️PascalCase
Class / component naming standard (C#, React, Java).
—
🐍snake_case
Python and database column/table naming standard.
—
🔗kebab-case
URL slug, CSS class, and file naming standard.
—
📌CONSTANT_CASE
Constant / environment variable naming standard (ENV).
—
🔵dot.case
Config keys, npm namespaces, and dotted file-naming standard.
—
🔃Invert Case
Flips the case of every letter (aA↔Aa) — unlike Reverse Text, the letter order doesn't change.
—

Find & Replace

Search for a word or phrase in your text above and replace every occurrence — with optional case-sensitive and whole-word matching. Runs entirely in your browser.

Type a term to find, an optional replacement, then click Replace all — the text box above is updated in place.

Case mode & developer format reference

Short definitions of every mode, and sample output for the developer formats.

6 core case modes
ModeDefinition
UPPERCASEConverts every letter to a capital letter
lowercaseConverts every letter to a small letter
Title CaseCapitalizes each main word; minor words stay lowercase
Sentence caseCapitalizes only the first letter of each sentence
aLtErNaTiNg cAsEAlternates lowercase/uppercase letter by letter
Reverse TextReverses the entire text, letter by letter
Developer formats applied to "first name and last name"
FormatExampleTypical use
camelCasefirstNameAndLastNameJS/Java variable
PascalCaseFirstNameAndLastNameClass / component name
snake_casefirst_name_and_last_namePython / DB column
kebab-casefirst-name-and-last-nameURL slug / CSS class
dot.casefirst.name.and.last.nameConfig key / npm namespace
CONSTANT_CASEFIRST_NAME_AND_LAST_NAMEConstant / ENV variable

Words are split on Unicode letter/number boundaries, so accented text splits correctly too.

Add this tool to your site (embed code)

Embed the text case converter on your own website for free. Copy the code below into your HTML — the tool runs in a simplified view and links back to this page as its source.

The embedded tool has a fixed layout; you can adjust the height value to fit your site. No ads or personal data, runs entirely client-side.

Text case terms glossary

Short definitions of the core terms used in this tool.

Title CaseCapitalizes the first letter of each main word; minor words (a, the, and, of…) stay lowercase unless first or last.
Sentence caseCapitalizes only the first letter of each sentence; everything else is lowercase.
Alternating CaseAlternates lowercase and uppercase letter by letter ("sPongeBob case"), used for humor or emphasis.
Invert CaseFlips the case of every letter (aA↔Aa) without changing letter order.
camelCaseFirst word lowercase, each following word capitalized, no spaces. Used for JS/Java variable names.
PascalCaseEvery word capitalized, no spaces. Used for class and component names.
snake_caseWords lowercase, separated by underscores. Common in Python and database columns.
kebab-caseWords lowercase, separated by hyphens. Common in URLs and CSS classes.
dot.caseWords lowercase, separated by periods. Common in config keys and npm package namespaces.
CONSTANT_CASEWords uppercase, separated by underscores. Used for constants and environment variables.
Minor wordA short article, conjunction, or preposition (a, an, the, and, of, in…) that stays lowercase in Title Case unless it starts or ends the title.

In-depth guides

Step-by-step explanations of the most common text-case questions.

How to fix text that's stuck in ALL CAPS

Paste the shouted text into the box above and click the lowercase tab to remove all capitalization, then switch to Sentence case to restore proper capitalization at the start of each sentence. This two-step approach works better than Sentence case alone, because Sentence case only capitalizes what follows sentence-ending punctuation — it won't lowercase words that were already in caps mid-sentence.

For a heading or product name instead of a paragraph, use Title Case after switching to lowercase, so each main word gets capitalized correctly.

Title Case vs. Sentence case — which one for headlines?

Use Title Case for headlines, article titles, product names, and navigation menu items — anywhere a short, formal label is expected. Use Sentence case for body copy, chat messages, and most UI labels in modern web and mobile design, where a more conversational, lowercase-heavy look is standard.

Many news sites and style guides (AP, Chicago) mix the two: headlines in Title Case, but subheadings or captions in Sentence case. The choice is a style decision, not a grammar rule — pick one and stay consistent within a document.

camelCase, PascalCase, snake_case, and kebab-case — which format for which use case?

The right naming format depends on where the name is used: camelCase for JavaScript/Java/Swift variables and function names, PascalCase for classes, React components, and TypeScript interfaces, snake_case for Python identifiers and SQL/database columns, kebab-case for URL slugs and CSS class names (hyphens are safe in URLs, underscores are not always), dot.case for configuration keys and npm package namespaces (e.g. eslint.config), and CONSTANT_CASE for constants and environment variables (e.g. API_KEY).

Mixing formats within the same codebase is a common source of bugs and inconsistency — pick the convention your language or framework expects and apply it everywhere.

Frequently asked questions

How do I convert text to UPPERCASE?
Paste your text into the box and click the UPPERCASE tab; every letter is converted instantly and you can copy the result with one click. The conversion happens entirely in your browser — your text is never sent to a server.
What is Title Case, and which words stay lowercase?
Title Case capitalizes the first letter of each main word in a title. This tool keeps short minor words — like "a", "an", "the", "and", "or", "of", "in", "to" — lowercase in the middle of a title, while the first and last word are always capitalized. So "the quick fox and the lazy dog" becomes "The Quick Fox and the Lazy Dog", not every word capitalized.
How do I convert text to lowercase?
Switch to the lowercase tab; the entire text is converted to lowercase letters and you can copy the result. This is a quick way to fix text that was accidentally typed with Caps Lock on.
What is Sentence case, and how does it work?
Sentence case capitalizes only the first letter of each sentence and lowercases everything else. The tool detects sentence boundaries after periods, question marks, exclamation points, ellipses, or line breaks, then capitalizes the next letter — the fastest way to turn a block of shouted or randomly-cased text into normal sentences.
Does the text case converter support accented and special characters?
Yes. Letters with accents or diacritics — like café, naïve, résumé — are handled correctly in every mode: UPPERCASE, lowercase, Title Case, Sentence case, Alternating case, and Reverse Text. Words are never split incorrectly.
How do I use camelCase and snake_case formats?
The Developer formats section automatically converts the same text into camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE. These formats are used for variable names, file names, CSS classes, and API field names — each one has its own copy button.
Is my text sent to a server?
No. All conversion happens locally in your browser using JavaScript; your text is never uploaded or stored anywhere. Only if you click Share or Copy link is the text optionally encoded into the page's URL, and very long text is trimmed before that happens.
What is Alternating Case used for?
Alternating Case (also called "sPongeBob case") switches every letter between lowercase and uppercase in sequence. It's mostly used for humor, sarcasm, or emphasis on social media, and doesn't change the meaning of the text — only its appearance.
What is dot.case, and when is it used?
dot.case lowercases every word and joins them with periods instead of spaces, hyphens, or underscores — for example "first name" becomes "first.name". It's commonly used for configuration keys, npm package namespaces, and some file-naming conventions. The Developer formats section generates it automatically alongside camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE.
How do I remove duplicate lines or line breaks from text?
Use the Remove duplicate lines button in the toolbar to delete repeated lines while keeping the first occurrence of each, or the Remove line breaks button to join every line into a single line separated by spaces. Both run instantly on the text in the box, entirely in your browser.

Methodology & sources

ToolPico's Text Case Converter is a free, independent, browser-based text formatting tool. UPPERCASE and lowercase conversion use JavaScript's standard toUpperCase() / toLowerCase() methods. Word boundaries for Title Case, Sentence case, and the developer formats are detected with Unicode-aware letter/number matching (\p{L}\p{N}), so accented and non-English letters split correctly. Title Case keeps a fixed list of common English minor words (a, an, the, and, but, or, nor, as, at, by, for, from, if, in, into, of, on, onto, over, to, up, with, yet, so) lowercase unless they open or close the title — a standard convention used by most style guides.

Basis: Standard JavaScript string methods and common English title-case style-guide conventions. Last updated: July 19, 2026. All processing happens client-side, in your browser; no text is sent to or stored on a server.

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