Cymath - Solve equations, differentiate, expand, factor, graph, integrate, simplify, asymptotes, completing the square, degree/radian conversion, domain/range, evaluate, GCF, LCM, polynomial division, prime factorization, simplify/evaluate fractions, inequalities, and decimal/fraction/percent conversions; this site will not only show the answer, but show the steps in obtaining it
Desmos Calculators:
GeoGebra Calculators - Includes CAS - Computer Algebra System (a powerful tool that solves mathematical equations and manipulates algebraic expressions symbolically [e.g., giving an exact answer like (2x + 5x = 7x)], rather than just providing numerical decimals), Graphing, Scientific, Geometry, Probability, and 3D Calculators
Graphing Calculator Emulators - Popular models such as the TI-83 Plus, TI-86, and the TI-89 are emulated right in your web browser
Google Math Solver - Calculator, solve equations, complex numbers, trigonometry, inequalities, systems of linear equations, exponents, radicals, absolute value, logarithms, probability, integrals, derivatives, vectors, and matrices
Fraction Calculator - Add, subtract, multiply, and divide fractions, including mixed numbers; simplify fractions; convert between fractions and decimals
Graph Paper - Print the following sheets of graph paper to plot points or produce graphs on the x-y coordinate plane: