# Desmos

Desmos is an advanced graphing calculator implemented as a web application and a mobile application written in TypeScript and JavaScript.

## History

Desmos was founded by Eli Luberoff, a math and physics double major from Yale University, and was launched as a startup at TechCrunch's Disrupt New York conference in 2011. As of September 2012, it had received around 1 million US dollars of funding from Kapor Capital, Learn Capital, Kindler Capital, Elm Street Ventures and Google Ventures.
The name Desmos came from the Greek word δεσμός which means a bond or a tie.
In May 2022, Amplify acquired the Desmos curriculum and teacher.desmos.com. Some 50 employees joined Amplify. Desmos Studio was spun off as a separate public benefit corporation focused on building calculator products and other math tools.
In May 2023, Desmos released a beta for a remade Geometry Tool. In it, geometrical shapes can be made, as well as expressions from the normal graphing calculator, with extra features. In September 2023, Desmos released a beta for a 3D calculator, which added features on top of the 2D calculator, including cross products, partial derivatives and double-variable parametric equations.

## Features

In addition to graphing both equations and inequalities, it also features lists, plots, regressions, interactive variables, graph restriction, simultaneous graphing, piecewise function graphing, recursive function graphing, polar function graphing, two types of graphing grids – among other computational features commonly found in a programmable calculator. It can also be used in several languages. Calculus operations such as derivatives and integrals are also available, although direct limits are currently absent. Integrations to positive and negative infinity are supported, and series can also be raised to sufficiently high iterations. Other functions like trigonometric and other transcendental functions, as well as the error function, factorial, statistical operations such as the normal distribution, chi-squared, the aforementioned regressions, the random function, and recursive functions have also been introduced since 2020. In November 2023, Desmos gave users the ability to bring sound to their graphs, allowing them to produce tones of a given frequency and gain.
Users can create accounts and save the graphs and plots that they have created to them. A permalink can then be generated which allows users to share their graphs and elect to be considered for staff picks. The tool comes pre-programmed with 36 different example graphs for the purpose of teaching new users about the tool and the mathematics involved.
As of April 2017, Desmos also released a browser-based 2D interactive geometry tool, with supporting features including the plotting of points, lines, circles, and polygons. In May 2023, Desmos released a beta version of a second, more sophisticated geometry calculator.
Another popular use of the calculator involves the creation of graphic arts using equations and inequalities. Some of these projects have included features such as 3D via parameterization, and with the use of RGB and HSV colouring introduced in late 2020, artwork with custom colouring, as well as the domain colouring of complex functions. With new performance updates, graphs that include the Mandelbrot set and the Ducks fractal can be made on Desmos. Features such as simulations and tickers also allowed users to create functional interactive games. The usage of these features can be found in Desmos's annual art contest.
Desmos also offers other services: the Scientific Calculator, Four Function Calculator, Matrix Calculator, Geometry Tool, Geometry Calculator, 3D Graphing Calculator, and Desmos Test Mode.

## Applications

A modified version of the calculator has been used in standardized tests, such as the State of Texas Assessments of Academic Readiness test, the Virginia Standards of Learning (SOL), the California Assessment of Student Performance and Progress (CAASPP) and the SAT. On the upcoming 2025 AP Exams, the calculator will be available in all exams where a calculator is required or optional, except AP Statistics and on exams taken in Kansas or New Jersey. Activity modules for classrooms can be created through a teacher account, which allow instructors to view students' work and response in real-time.
Its business model involves paid partnerships with publishers, assessment companies, and educational institutions.
The calculator and graphing features can also be found on AssessPrep, an examination site used by many schools following the IB Curriculum.