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CatToolKit

Cat-themed developer tools that run entirely in your browser. Fast, private, and purrfectly simple.

Explore tools
Data stays on deviceNo signupFree forever

Text & Data

JSON Formatter & Validator

Format, validate, and beautify your JSON data with syntax highlighting.

Word & Character Counter

Count words, characters, sentences, and paragraphs in your text.

Text Case Converter

Convert text between UPPERCASE, lowercase, Title Case, camelCase, and more.

Diff Checker

Compare two texts and see the differences highlighted line by line.

Encoding & Decoding

Base64 Encoder & Decoder

Encode text to Base64 or decode Base64 strings back to plain text.

URL Encoder & Decoder

Encode or decode URLs and query parameters for safe transmission.

HTML Entity Encoder & Decoder

Encode special characters to HTML entities or decode entities back to text.

Generators

UUID Generator

Generate random UUIDs (v4) in bulk. Copy with one click.

Lorem Ipsum Generator

Generate placeholder text in paragraphs, sentences, or words.

Barcode Generator

Generate barcodes in batch — sequential or custom list. Export as PDF or PNG.

Security & Crypto

Hash Generator (MD5, SHA)

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text.

Password Generator

Create strong, random passwords with customizable length and character types.

JWT Decoder

Decode and inspect JSON Web Tokens (JWT) — header, payload, and signature.

Converters

Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and vice versa.

JSON to CSV Converter

Convert JSON arrays to CSV format and download the result.

Web & Dev

Color Picker & Converter

Pick colors and convert between HEX, RGB, and HSL formats.

Markdown Preview

Write Markdown and see the rendered HTML preview in real time.

Regex Tester

Test and debug regular expressions with real-time matching and group highlighting.