Free & browser-based
Math tools that just work.
No signups, no clutter, no installs. A suite of 12+ free online calculators, simulators, and solvers, starting with a fast, interactive graphing calculator.
Why people use profpi
Built to be fast, honest, and free of the noise most tools bury you in.
Instant, no signup
Open a tool and start working immediately. No accounts, no email, no paywalls.
Runs in your browser
Every tool is self-contained client-side software — nothing to install, nothing running on a server.
Works on any device
Every tool is built responsive from the ground up, so it feels native on desktop, tablet, and phone.
Light & dark mode
Every tool respects the way you like to work, day or night, with a single tap.
Tools
Choose from our suite of 12+ calculators, simulators, and visual solvers.
ODE & Phase Portrait
Plot slope fields, trajectories, and automatically classify equilibria (saddles, nodes, spirals).
Open toolNeural Network Playground
Train a real neural network in your browser and watch backpropagation learn step by step.
Open toolComplex Plane
Type a complex function and see it rendered live as a domain-coloring map with poles and zeros marked.
Open toolFourier Explorer
Draw any shape, or type a parametric curve, and watch a chain of rotating epicycles trace it in real time.
Open toolNeural ODE
Train a tiny neural network to learn a differential equation's vector field from sampled data.
Open toolGraphing Calculator
Plot functions, trace exact points, zoom and pan, and explore math interactively.
Open toolSymbol Dictionary & LaTeX
Search math symbol meanings, copy LaTeX codes, and test expressions in the live KaTeX editor.
Open toolFraction Visualizer
Add, subtract, compare, and divide fractions step-by-step with interactive pie and bar models.
Open toolEquation Finder
Fit a curve (linear, quadratic, exponential, logarithmic) to your coordinate points and find the best formula.
Open toolGeometry Solver
Solve angles, sides, areas, and perimeters of triangles, circles, and rectangles with to-scale drawings.
Open toolNumber Pattern Solver
Solve sequence rules (arithmetic, geometric, quadratic, Fibonacci) to get explicit and recursive formulas.
Open toolUnit Circle Explorer
Visualize trig functions, drag points to change angles, and snap to common radian/degree values.
Open toolDivision Visualizer
Solve long division problems step-by-step with structured grids showing subtraction lines and remainders.
Open toolDaily Math Puzzle
Solve today's math riddle! Test your skills, verify answers instantly, and share results with friends.
Open toolProbability Simulator
Flip virtual coins, roll dice, and draw cards. Compare experimental rates to theoretical percentages.
Open toolBase Converter
Convert numbers between binary, octal, decimal, and hexadecimal with step-by-step divisions.
Open toolMental Math Trainer
Test your arithmetic calculation speed. Solve equations against a 60-second timer challenge.
Open toolWord Problem Diagrammer
Generate to-scale tape diagrams and bar models for word problem ratios. Download as SVG/PNG.
Open tool