Web Development Calculators
HTML escape, URL encode, Base64, JSON formatter, and word counter.
Explore our collection of free web development calculators and tools. Each calculator runs instantly in your browser, works offline, and includes detailed explanations, formulas, and examples. Choose a tool below to get started.
HTML Escape / Unescape
Convert special characters to HTML entities and back.
URL Encoder / Decoder
Encode and decode URLs and query parameters safely.
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 to text.
JSON Formatter & Validator
Format, validate, and pretty-print JSON data.
Word Counter
Count words, characters, sentences, and paragraphs.
Hex to Decimal Converter
Convert hexadecimal numbers to decimal, binary, and octal. Supports signed and unsigned values.
Binary Calculator
Add, subtract, multiply, and divide binary numbers. Convert between binary, decimal, and hex.
Subnet Calculator
Calculate IP subnets, CIDR ranges, network addresses, broadcast addresses, and host counts.