1. fxSolver is an free online math solver, equation library, graphing calculator and science/engineering problem helper. To get started, add some formulas, fill in any input variables and press "Solve."

  2. SpeedCrunch. SpeedCrunch is a high-precision scientific calculator featuring a fast, keyboard-driven user interface. It is free and open-source software, licensed under the GPL. Download Documentation DonateĀ .

  3. The built in Calculator on the iPhone.

  4. Any individual who has ever gazed restlessly at a knotty condition needing an answer has longed for some sort of hatchet to slice through the issue.

  5. WolframAlpha brings expert-level knowledge and capabilities to the broadest possible range of peopleā€”spanning all professions and education levels.

  6. Mathway is a freemium math solving app that helps you find the solutions to any math problem you can imagine.

  7. Numi Organic Tea is a premium, Fair Trade sustainable company specializing in unique and innovative blends of green, black, white, oolong teas, Pu-erh, rooibos, herbal and Flowering Teaā„¢.

  8. Calcbot is a simple and beautifully designed calculator for your iPhone, iPod touch and iPad.

  9. Math, LibreOffice, math editor, ODF, OpenFormula, open standards

  10. RealCalc Scientific Calculator

  11. Equation editor

  12. Learn and help others learn