Molecule library

Build a molecule to see its properties.

⚛️ Quantum calculation · GFN2‑xTB

xTB = fast semi‑empirical · DFT/HF run real QM on our server · NMR is an empirical ¹H/¹³C prediction.

🌀 Orbitals & ESP · HF/3‑21G

Computes the molecular orbitals on our server (Psi4) and renders the isosurfaces — blue/red lobes are the orbital phases. Small molecules only; takes a bit longer.

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Properties computed in your browser with RDKit. Drug-likeness rules are guidelines, not verdicts.

Chemistry calculators

The everyday math — balance equations, molar mass, mole conversions, dilutions, gas laws, pH.

Equation balancer

Type an equation with → or =, e.g. C3H8 + O2 -> CO2 + H2O.

Molar mass & mole converter

Handles parentheses and hydrates, e.g. Ca(OH)2, CuSO4·5H2O.

Dilution & gas law

C₁V₁ = C₂V₂ — leave one box blank, it's solved.

PV = nRT — leave one box blank. R = 0.0821.

pH & Beer–Lambert

pH of a strong acid/base from its concentration (mol/L).

Beer–Lambert A = ε·b·c — leave one box blank.

Want a human to walk through it?

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