Online Science Tools
Free chemistry and math calculators for coursework — chemical equilibrium, pH, stoichiometry, equation balancing, buffers, graphing, phase portraits, and short study guides. No account required.
Chemistry
Reactions & stoichiometry
5- Chemical Equation BalancerBalance chemical equations and get the smallest whole-number coefficients, steps, and an atom-check table.
- Stoichiometry CalculatorCalculate molar mass and convert between moles, grams, and particles for chemical formulas.
- Limiting Reagent CalculatorFind the limiting reagent, theoretical yield, and percent yield from a balanced equation and starting amounts.
- Composition & Empirical Formula CalculatorGet mass percent composition from a formula, or find empirical and molecular formulas from percent data.
- Redox Equation BalancerBalance redox equations in acidic or basic medium with atom and charge conservation (H₂O / H⁺ / OH⁻).
Solutions & concentration
2Equilibrium & acids
4- Chemical Equilibrium CalculatorChemical equilibrium calculator for Kc/Kp, reaction quotient Q, ICE tables, and equilibrium concentrations.
- pH CalculatorpH and pOH calculator from concentration and Ka/Kb—strong/weak acids and bases (including ammonia, Kb = 1.8×10⁻⁵) and simple buffers via Henderson–Hasselbalch.
- Phosphate Buffer CalculatorPhosphate buffer calculator (plus acetate, Tris, citrate, and more)—grams from target pH, total concentration, and volume via Henderson–Hasselbalch.
- Ksp CalculatorCalculate Ksp from molar solubility, find solubility from Ksp, and compare Q with Ksp to predict precipitation.
Energy, rates & electrochemistry
3- Thermochemistry CalculatorCompute ΔH° from formation enthalpies, apply Hess’s law, run calorimetry q = mcΔT, and scale heat with moles.
- Kinetics CalculatorKinetics calculator for half-life and integrated rate laws—solve for concentration, time, or k in zero-, first-, and second-order reactions.
- Nernst Equation CalculatorCalculate non-standard cell potential E from E°, n, and Q, plus ΔG = −nFE.
Mathematics
Graphing & dynamics
3- Phase Portrait GeneratorVisualize 2D autonomous differential equation systems with vector fields and trajectories.
- 2D Graphing CalculatorPlot y = f(x) with adjustable windows and local extrema markers.
- Time Graphing ToolAnimate functions of time and parametric trajectories with a playable t parameter.
Computing
Web & numbers
3- Binary Calculator & ConverterConvert and compute across binary, octal, decimal, and hexadecimal number systems.
- Hex Color Picker & ConverterPick colors and convert between HEX, RGB, and HSL for web workflows.
- Online HTML / JS ExecutorWrite and run HTML, CSS, and JavaScript in a sandboxed browser playground.
Guides
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