string-conv

A lightweight, zero-dependency TypeScript utility for string case conversion, inspection, and manipulation. Convert strings between 18+ formats, detect case styles with validation guards, and use robust utilities for everyday string tasks. Works in both JavaScript and TypeScript projects.

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Features

• ✅ Zero dependencies — Extremely lightweight.
• ✅ Full TypeScript Support — Built-in type declarations included.
• ✅ Hybrid Package — Works seamlessly with ESM (import) and CommonJS (require).
• ✅ Robust Case Handling — Handles edge cases like multiple spaces, special characters, and mixed-case inputs.
• ✅ Case Detection — Identify case styles programmatically.
• ✅ Advanced Utilities — Built-in support for HTML stripping, palindromes, truncation, and more.

Installation

npm install string-conv

Usage

TypeScript / ESM

import {
  // Case transforms
  toUpperCase,
  toLowerCase,
  toTitleCase,
  toSentenceCase,
  toCamelCase,
  toPascalCase,
  toSnakeCase,
  toKebabCase,
  toConstantCase,
  toDotCase,
  toSlug,
  fromSlug,
  toInverseCase,
  toReverseCase,
  toTrainCase,
  toPathCase,
  toFlatCase,
  toHeaderCase,
  toSpongeCase,
  // Inspection
  detectCase,
  isCamelCase,
  isPascalCase,
  isSnakeCase,
  isKebabCase,
  isConstantCase,
  isDotCase,
  isTrainCase,
  isPathCase,
  // Utilities
  truncate,
  wordCount,
  charCount,
  countOccurrences,
  reverseWords,
  trimWords,
  padStart,
  padEnd,
  stripHtml,
  isPalindrome,
  escapeHtml,
} from "string-conv";

JavaScript (CommonJS)

const {
  toUpperCase,
  toLowerCase,
  toTitleCase,
  toSentenceCase,
  toCamelCase,
  toPascalCase,
  toSnakeCase,
  toKebabCase,
  toConstantCase,
  toDotCase,
  toSlug,
  fromSlug,
  toInverseCase,
  toReverseCase,
  toTrainCase,
  toPathCase,
  toFlatCase,
  toHeaderCase,
  toSpongeCase,
  detectCase,
  isCamelCase,
  isPascalCase,
  isSnakeCase,
  isKebabCase,
  isConstantCase,
  isDotCase,
  isTrainCase,
  isPathCase,
  truncate,
  wordCount,
  charCount,
  countOccurrences,
  reverseWords,
  trimWords,
  padStart,
  padEnd,
  stripHtml,
  isPalindrome,
  escapeHtml,
} = require("string-conv");

API — Case Transforms

toUpperCase(str: string): string

Converts a string to UPPERCASE.

toUpperCase("hello world"); // => "HELLO WORLD"

toLowerCase(str: string): string

Converts a string to lowercase.

toLowerCase("HELLO WORLD"); // => "hello world"

toTitleCase(str: string): string

Converts to Title Case (first letter of each word capitalized).

toTitleCase("hello world"); // => "Hello World"

toSentenceCase(str: string): string

Capitalizes only the first character.

toSentenceCase("hello world"); // => "Hello world"

toCamelCase(str: string): string

toCamelCase("hello world"); // => "helloWorld"

toPascalCase(str: string): string

toPascalCase("hello world"); // => "HelloWorld"

toSnakeCase(str: string): string

toSnakeCase("hello world"); // => "hello_world"

toKebabCase(str: string): string

toKebabCase("hello world"); // => "hello-world"

toConstantCase(str: string): string

toConstantCase("hello world"); // => "HELLO_WORLD"

toDotCase(str: string): string

toDotCase("hello world"); // => "hello.world"

toInverseCase(str: string): string

Inverts character casing.

toInverseCase("Hello World"); // => "hELLO wORLD"

toReverseCase(str: string): string

Reverses characters.

toReverseCase("hello"); // => "olleh"

toTrainCase(str: string): string

toTrainCase("hello world"); // => "Hello-World"

toPathCase(str: string): string

toPathCase("hello world"); // => "hello/world"

toFlatCase(str: string): string

toFlatCase("Hello World"); // => "helloworld"

toHeaderCase(str: string): string

toHeaderCase("content type"); // => "Content-Type"

toSpongeCase(str: string): string

toSpongeCase("hello"); // => "hElLo" (random)

API — Inspection

detectCase(str: string): CaseType

Detects the case style of a string.

detectCase("helloWorld"); // => "camelCase"

Possible values: "camelCase", "PascalCase", "snake_case", "kebab-case", "CONSTANT_CASE", "dot.case", "path/case", "Train-Case", "Title Case", "UPPERCASE", "lowercase", "unknown".

Validation guards

Boolean checks for specific styles: isCamelCase, isPascalCase, isSnakeCase, isKebabCase, isConstantCase, isDotCase, isTrainCase, isPathCase.

API — Utilities

stripHtml(str: string): string

Removes HTML tags.

stripHtml("<p>Hello <b>World</b></p>"); // => "Hello World"

isPalindrome(str: string, ignoreSpaces?: boolean): boolean

isPalindrome("racecar"); // => true

escapeHtml(str: string): string

escapeHtml("<b>Hi</b>"); // => "&lt;b&gt;Hi&lt;/b&gt;"

truncate(str: string, maxLength: number, suffix?: string): string

truncate("Hello, World!", 8); // => "Hello..."

wordCount(str: string): number

wordCount("hello world"); // => 2

reverseWords(str: string): string

reverseWords("hello world"); // => "world hello"

trimWords(str: string): string

Collapses internal whitespace.

trimWords("  hello   world  "); // => "hello world"

Quick Reference Table

| Function | Input | Output | | :--------------- | :-------------- | :-------------- | | toUpperCase | "hello world" | "HELLO WORLD" | | toLowerCase | "HELLO WORLD" | "hello world" | | toTitleCase | "hello world" | "Hello World" | | toSentenceCase | "hello world" | "Hello world" | | toCamelCase | "hello world" | "helloWorld" | | toPascalCase | "hello world" | "HelloWorld" | | toSnakeCase | "hello world" | "hello_world" | | toKebabCase | "hello world" | "hello-world" | | toConstantCase | "hello world" | "HELLO_WORLD" | | toDotCase | "hello world" | "hello.world" | | toInverseCase | "Hello World" | "hELLO wORLD" | | toTrainCase | "hello world" | "Hello-World" | | toPathCase | "hello world" | "hello/world" | | toFlatCase | "Hello World" | "helloworld" |

License

MIT © Chetan Nada