Web & developer files

HTTP status codes, MIME types, file extensions, HTML entities and CSS units for developers.

• ASCII printable characters Full ASCII table with decimal, hex and binary codes, control-character names, and printable symbols — look up any character code instantly online.
• Common HTTP headers The 15 most common HTTP headers, their direction (request, response or both), and what each one is for — a quick developer lookup.
• Common MIME types Content-Type values for web pages, documents, images, audio, and video — with the file extensions they usually pair with. Pick the right header every time.
• Common network ports quick reference TCP/UDP ports for FTP, SSH, HTTP, HTTPS, email and databases, with a plain-English purpose for firewalls and debugging.
• CSS size units (px rem em vh) When to use px, rem, em, %, vw/vh and other CSS length units — quick guidance on each. Pick the right CSS unit for your next layout in seconds.
• Common file extensions What popular file extensions usually mean on the desktop and the web — from .pdf and .zip to .exe and .svg. Identify any file instantly at a glance.
• Git commands cheatsheet The 15 Git commands you use every day: init, clone, commit, branch, merge, rebase, push and more — each explained in a single, copy-friendly line.
• HTML character entities Common HTML entities for symbols, punctuation, and whitespace, with their entity names. Copy the code you need without hunting through reference tables.
• HTTP request methods explained HTTP request methods GET, POST, PUT, PATCH and DELETE: what each one does, whether it is safe and idempotent, and which success status a REST API returns.
• HTTP status codes quick reference Common HTTP response status codes with short, plain-English meanings for 200, 404, 500 and more. A quick reference for API development and debugging.
• Keyboard shortcuts The 14 most useful keyboard shortcuts for Windows, Linux and macOS — copy, paste, undo, find, screenshot and lock screen.
• Number bases (decimal hex binary) Convert decimal, hexadecimal, binary and octal instantly — full 0–32 chart, bit basics, and 0x/0b prefixes for programmers, students and engineers.
• Regex basics cheatsheet Regular-expression cheatsheet: the most useful tokens with a copy-paste example for each, ready for search and validate work.
• Roman numerals reference Roman numerals 1–1000 with an instant converter, subtractive-notation rules, and common years like 2026 (MMXXVI) — find any numeral at a glance.