Wolfram|Alpha is a computational knowledge engine that provides instant expert knowledge and computation across thousands of domains. It uses a vast collection of algorithms and data to compute answers and generate reports for users. Wolfram|Alpha covers a wide range of domains, including mathematics, statistics and data analysis, physics, chemistry, materials, engineering, astronomy, earth science, life sciences, computational sciences, units and measures, dates and times, weather, places and geography, people and history, culture and media, music, words and linguistics, sports and games, colors, money and finance, socioeconomic data, health and medicine, food and nutrition, education, organizations, transportation, technological world, and web and computer systems.

Wolfram|Alpha is used in the Apple Siri Assistant, which gives users access to the full power of the computational knowledge engine. The domains covered by Wolfram|Alpha include elementary math, numbers, plotting, algebra, matrices, calculus, geometry, trigonometry, discrete math, number theory, applied math, logic functions, definitions, descriptive statistics, regression, statistical distributions, probability, mechanics, electricity and magnetism, optics, thermodynamics, relativity, nuclear physics, quantum physics, particle physics, statistical physics, astrophysics, physical constants, elements, compounds, ions, quantities, solutions, reactions, chemical thermodynamics, protecting groups, alloys, minerals, crystallography, plastics, woods, bulk materials, acoustics, aeronautics, electric circuits, fluid mechanics, steam tables, psychrometrics, refrigeration, structures, star charts, astronomical events, planets, moons, minor planets, comets, space weather, stars, pulsars, galaxies, star clusters, nebulae, astrophysics, geology, geochronology, geodesy, earthquakes, tide data, atmosphere, climate, animals and plants, dinosaurs, DNA sequence lookup, SNPs, proteins, human, mouse and fruit fly genomes, metabolic pathways, cellular automata, substitution systems, Turing machines, computational complexity, algebraic codes, fractals, Mathematica, image processing, conversions, comparisons, dimensional analysis, industrial measures, batteries, paint, date computations, time zones, calendars, holidays, geological time, current and historical weather, forecasts, wind chill, hurricanes, clouds, climate, maps, projections, geodesy, navigation, distances, geomagnetism, geocoding, countries, cities, elevation data, oceans, lakes, rivers, islands, mountains, people, genealogy, names, occupations, political leaders, historical events, periods and countries, historical numerals and money, books, periodicals, movies, video games, fictional characters, mythology, television networks and programs, awards, musical notes, intervals, chords, scales, audio waveforms, instruments, songs, word properties, dictionary lookup, word puzzles, anagrams, languages, document length, Morse code, Soundex, number names, football, baseball, Olympics, stadiums, lotteries, card games, color names and systems, color addition, temperatures, wavelengths, stock data, indices, mutual funds, futures, mortgages, present value, currency conversion, tips, bonds, derivatives valuation, wages, sales tax, demographics, economics, agriculture, energy, salaries, unemployment, cost of living, health care, housing, social statistics, crime, military, religion, body measurements, growth charts, exercise, diseases, mortality data, medical test data, teeth, vision, drug data, hospitals, foods, dietary references, international education, universities, school districts, public schools, standardized tests, companies, hospitals, foundations, international organizations, airports, airlines, aircraft, flight data, road transport, gasoline prices, bridges, tunnels, tides, communications, satellites, space probes, photography, barcodes, website data, IP lookup, notable computers, data transfer, port numbering, string processing, hashing, and Unicode lookup.