# Case Converter

> Convert text to camelCase, snake_case, PascalCase & kebab-case, or just quickly to UPPERCASE or lowercase. For developers and everyday writing. Free and online.

URL: https://acrafto.com/en/case-converter/

Tools are interactive browser apps; there is no public API, no endpoints to call and no server-side processing. To use a tool, open its HTML page in a browser.

Need to quickly rewrite a headline in ALL CAPS, or tame the Caps Lock that got left on halfway through an email? Or maybe you’re wondering what a variable you’d normally write with underscores in Python should look like in JavaScript? Our **Case Converter** handles both — one click rewrites your text into every common everyday and programming format at once.

Our tool is a Swiss Army knife for text formatting. Just type your text once (in any format), and we’ll instantly rewrite it into the nine other variants.

## Quick uppercase/lowercase conversion (no coding required)

The most common use is also the simplest: you just need text **all in caps**, **all in lowercase**, or neatly formatted for a heading.

- **UPPERCASE:** Ideal for headings, logos, alerts, or forms that require capital letters (e.g. an address on an envelope).
- **lowercase:** Great for cleaning up data — say, when someone sends you an email address or username typed in a random mix of CapItaLS and you need to normalize it.
- **Title Case:** Every Word Starts With A Capital Letter — used for article headlines, product names, or presentations in the Anglo-American style.
- **Sentence case:** Only the first letter of the sentence is capitalized, the rest is lowercase — exactly how a standard English sentence is written.

Just paste your text into the box, pick the format you need, and hit **Copy**. No manually undoing Caps Lock or retyping letter by letter.

## Quick overview: which case to use in programming?

If you code and aren’t sure which naming convention applies where, here’s a cheat sheet:

### 🐪 camelCase (Camel Notation)

Starts with a lowercase letter, and each subsequent word begins with an uppercase letter. No spaces.

- **Where it’s used:** JavaScript, Java, Swift, Kotlin, Go.
- **Examples:** `myVariableName`, `getElementById`, `iPhone`.

### 🐍 snake\_case (Snake Notation)

All letters are lowercase and separated by underscores.

- **Where it’s used:** Python, Rust, PHP, SQL databases, file names.
- **Examples:** `user_id`, `first_name`, `def my_function()`.

### 🍢 kebab-case (Kebab Notation)

Lowercase letters separated by hyphens. Looks like meat on a skewer.

- **Where it’s used:** CSS classes, HTML attributes, URLs (slugs), Kubernetes.
- **Examples:** `font-size`, `my-cool-article`, `<div id="main-content">`.

### 📐 PascalCase (UpperCamelCase)

Similar to camelCase, but the **first letter is uppercase**.

- **Where it’s used:** Class names in most languages (JS, Python, PHP), C# (methods and variables), React components.
- **Examples:** `UserProfile`, `AppController`, `ReactComponent`.

### 📢 CONSTANT\_CASE (Screaming Snake Case)

Uppercase letters separated by underscores. It screams at you that this value should not change.

- **Where it’s used:** Constants, ENV variables, global configurations.
- **Examples:** `MAX_RETRIES`, `API_KEY`, `DB_PASSWORD`.

---

## How does our converter work?

Our tool is “smart.” That means it doesn’t just blindly replace spaces or change letters one by one.

1. **Word detection:** The algorithm recognizes individual words, whether they’re separated by spaces (`hello world`), underscores (`hello_world`), hyphens (`hello-world`), or a shift to a capital letter (`helloWorld`).
2. **Normalization:** Everything is converted to a base form, regardless of how the text was originally written.
3. **Generation:** It assembles all the variants at once — from plain upper/lowercase to the full set of programming conventions.

This is handy, for example, when refactoring code and you need to turn an old PHP variable (`$user_id`) into modern JavaScript (`userId`) or build a CSS class (`user-id`) from a database column name. But it works just as well for everyday writing, whenever you need to quickly normalize letter casing without opening Word or Excel.

## FAQ: Frequently Asked Questions

### How can I convert text to uppercase online without retyping it by hand?

Paste your text into the box above and choose the **UPPERCASE** format. The tool instantly converts the whole text to capital letters — it also works with accented characters — and you can copy the result right away.

### What is "Hungarian notation"?

This is an older naming convention (common in C/C++ in the 90s) where a variable name starts with an abbreviation of its data type. For example, `strName` (string) or `iCount` (integer). It's not widely used in modern languages today because IDEs automatically show us the types.

### Can I use kebab-case in JavaScript?

Not directly as a variable name, because the hyphen `-` acts as a subtraction operator in JS. `var my-variable` would mean "my minus variable." Kebab-case is only used in JS as keys in objects, if they are in quotes: `{ "content-type": "json" }`.

### Which case should I use for JSON?

The JSON standard doesn't specify a case, but Google and most REST APIs use **camelCase** (e.g., `createdAt`). Conversely, some older APIs and Python backends return **snake\_case** (e.g., `created_at`). It's important to be consistent.

### Can the converter fix text typed with Caps Lock accidentally left on?

Yes. If you paste text that came out fully (or partially) reversed, just choose the **lowercase** format, then **Sentence case** if needed, so the first letter of the sentence stays capitalized as in normal writing.

## Other languages

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- Deutsch (de): [Case Converter](https://acrafto.com/de/case-converter/) ([Markdown](https://acrafto.com/de/case-converter/index.md))
- Français (fr): [Convertisseur majuscule minuscule](https://acrafto.com/fr/convertisseur-de-cas/) ([Markdown](https://acrafto.com/fr/convertisseur-de-cas/index.md))
- Español (es): [Convertidor de mayúsculas y minúsculas](https://acrafto.com/es/convertidor-de-casos/) ([Markdown](https://acrafto.com/es/convertidor-de-casos/index.md))
- Italiano (it): [Convertitore maiuscolo minuscolo](https://acrafto.com/it/convertitore-di-case/) ([Markdown](https://acrafto.com/it/convertitore-di-case/index.md))
- Português (pt): [Conversor de maiúsculas e minúsculas](https://acrafto.com/pt/conversor-de-casos/) ([Markdown](https://acrafto.com/pt/conversor-de-casos/index.md))
- Nederlands (nl): [Case converter](https://acrafto.com/nl/case-converter/) ([Markdown](https://acrafto.com/nl/case-converter/index.md))
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- Dansk (da): [Case converter](https://acrafto.com/da/case-konverter/) ([Markdown](https://acrafto.com/da/case-konverter/index.md))
- Suomi (fi): [Kirjainkoon muunnin](https://acrafto.com/fi/case-muunnin/) ([Markdown](https://acrafto.com/fi/case-muunnin/index.md))
- Norsk (no): [Case-konverterer](https://acrafto.com/no/case-konverterer/) ([Markdown](https://acrafto.com/no/case-konverterer/index.md))
- Українська (uk): [Конвертер регістру](https://acrafto.com/uk/konverter-registru/) ([Markdown](https://acrafto.com/uk/konverter-registru/index.md))
- Русский (ru): [Конвертер регистра](https://acrafto.com/ru/konverter-registrov/) ([Markdown](https://acrafto.com/ru/konverter-registrov/index.md))
- Српски (sr): [Konverter velikih i malih slova](https://acrafto.com/sr/pretvarac-formata-teksta/) ([Markdown](https://acrafto.com/sr/pretvarac-formata-teksta/index.md))
- Македонски (mk): [Конвертор на букви](https://acrafto.com/mk/konvertor-sluchai/) ([Markdown](https://acrafto.com/mk/konvertor-sluchai/index.md))
- Bosanski (bs): [Konverter velikih i malih slova](https://acrafto.com/bs/konverter-velicina-slova/) ([Markdown](https://acrafto.com/bs/konverter-velicina-slova/index.md))
- Shqip (sq): [Konvertues shkronjash](https://acrafto.com/sq/konvertues-rastesh/) ([Markdown](https://acrafto.com/sq/konvertues-rastesh/index.md))
- Türkçe (tr): [Büyük küçük harf dönüştürücü](https://acrafto.com/tr/case-converter/) ([Markdown](https://acrafto.com/tr/case-converter/index.md))
- 日本語 (ja): [大文字小文字変換](https://acrafto.com/ja/case-converter/) ([Markdown](https://acrafto.com/ja/case-converter/index.md))
- 한국어 (ko): [대소문자 변환기](https://acrafto.com/ko/case-converter/) ([Markdown](https://acrafto.com/ko/case-converter/index.md))
- العربية (ar): [تحويل الحروف الكبيرة والصغيرة](https://acrafto.com/ar/case-converter/) ([Markdown](https://acrafto.com/ar/case-converter/index.md))
- हिन्दी (hi): [केस कनवर्टर](https://acrafto.com/hi/case-converter/) ([Markdown](https://acrafto.com/hi/case-converter/index.md))
- Bahasa Indonesia (id): [Ubah huruf besar dan kecil](https://acrafto.com/id/konverter-case/) ([Markdown](https://acrafto.com/id/konverter-case/index.md))
- Tiếng Việt (vi): [Chuyển đổi chữ hoa thường](https://acrafto.com/vi/bo-chuyen-doi-kieu-chu/) ([Markdown](https://acrafto.com/vi/bo-chuyen-doi-kieu-chu/index.md))
- ไทย (th): [แปลงตัวพิมพ์ใหญ่และเล็ก](https://acrafto.com/th/case-converter/) ([Markdown](https://acrafto.com/th/case-converter/index.md))
- עברית (he): [המרת אותיות גדולות וקטנות](https://acrafto.com/he/case-converter/) ([Markdown](https://acrafto.com/he/case-converter/index.md))