Reference

Interactive periodic table with element details, atomic numbers, weights, and properties.

Complete table of element atomic weights for chemistry calculations and reference.

Electronegativity values for all elements using Pauling scale.

Genetic codon table showing mRNA codons and corresponding amino acids.

Decode resistor values using the standard color band system.

Calculate resistor values from color bands or find color codes from values.

Reference chart for ceramic and electrolytic capacitor markings.

Complete list of SI and metric unit prefixes from yocto to yotta.

Reference table of all seven SI base units and derived units.

Metric system prefixes with symbols and multiplication factors.

Complete ASCII character table with decimal, hex, and binary values.

Browse Unicode characters by block with code points and descriptions.

HTML entity codes for special characters, symbols, and accented letters.

Complete reference of HTTP status codes with meanings and use cases.

Email server response codes and their meanings for troubleshooting.

Reference for DNS record types including A, AAAA, CNAME, MX, TXT, and more.

Common network port numbers and their associated services.

File extension database with associated programs and MIME types.

MIME type reference for content type headers and file handling.

Universal keyboard shortcuts for common applications and operating systems.

Essential Vim commands and keyboard shortcuts for text editing.

Common Emacs keybindings and commands for efficient editing.

Essential Git commands for version control workflows.

Common Linux terminal commands for file management and system administration.

Windows CMD and PowerShell commands for system management.

macOS keyboard shortcuts for productivity and navigation.

Python built-in functions and types quick reference guide.

JavaScript built-in objects, methods, and global functions.

CSS properties organized by category with values and examples.

HTML5 elements with attributes, usage, and semantic meanings.

SQL statements and clauses for database queries and management.

Regular expression syntax, metacharacters, and common patterns.

Markdown formatting syntax for headers, lists, links, and more.

JSON format rules, data types, and structure guidelines.

YAML format syntax for configuration files and data serialization.

IEC binary prefixes (kibi, mebi, gibi) vs SI prefixes for data sizes.

Named colors with HEX, RGB, and HSL values for CSS and design.

Popular HEX color codes organized by color family.

216 web-safe colors that display consistently across browsers.

Web-safe font stacks and system font families for CSS.

Understanding DPI and PPI for print and screen resolution.

International paper sizes including A, B, C series and US formats.

Standard photo print dimensions and aspect ratios.

Common aspect ratios for video, photography, and displays.

Common screen resolutions from HD to 8K with aspect ratios.

Mobile and desktop viewport dimensions for responsive design.

Feature support across major browsers for web development.

World timezone abbreviations with UTC offsets and regions.

ISO country codes (2-letter and 3-letter) with country names.

ISO 639 language codes for internationalization.

ISO 4217 currency codes with symbols and country associations.

IBAN structure and formats by country for banking.

Look up manufacturer from MAC address OUI prefix.

IATA and ICAO airport codes with locations.

IATA airline codes and airline names reference.

International dialing codes by country.

Postal and ZIP code formats by country.

Roman numeral values and conversion reference.

Ordinal numbers in words (first, second, third, etc.).

Times tables from 1 to 12 in grid format.

List of prime numbers with primality checking.

Fibonacci numbers and the golden ratio relationship.

Triangular numbers sequence and formula.

Perfect squares from 1 to 100 and beyond.

Perfect cubes and cube root reference.

Common and natural logarithm values.

Sine, cosine, and tangent values for common angles.

Common unit conversions for length, weight, and volume.

Kitchen measurement conversions for cups, tablespoons, and more.

Common cooking ingredient substitutions and alternatives.

Baking temperatures and times for common foods.

Fahrenheit to Celsius and gas mark conversions.

Calorie counts for common foods and ingredients.

Essential vitamins with functions, sources, and daily values.

Essential minerals with health benefits and food sources.

Essential and non-essential amino acids with functions.

Blood pressure categories from normal to hypertensive.

Body Mass Index categories and health implications.

Training heart rate zones for exercise and fitness.

Rate of Perceived Exertion scale for workout intensity.

Common stretches by muscle group for flexibility.

Major muscle groups and exercises that target them.

Player positions for popular sports explained.

Popular chess openings with moves and strategies.

Scrabble tile point values and distribution.

Poker hands ranked from high card to royal flush.

Standard deck structure with suits and values.

Probability tables for common D&D dice rolls.

D&D ability score modifiers and stat explanations.

Zodiac signs with date ranges and characteristics.

Chinese zodiac animals by year with traits.

Lunar phases from new moon to full moon.

Solar system planets with distances and characteristics.

Stellar classification (O, B, A, F, G, K, M) with properties.

Periodic table trends for atomic radius, ionization energy, and more.

Electromagnetic spectrum from radio waves to gamma rays.

Radio communication phonetic alphabets and codes.

Alpha, Bravo, Charlie - the international spelling alphabet.

Morse code dots and dashes for letters and numbers.

Braille patterns for letters, numbers, and punctuation.