Free calculators and molecular structure tools with explicit inputs, visible methods, and stated limitations.
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Fast and accurate online tool for calculating compound molecular weight, supporting molecular formulas and SMILES input, widely used in chemical research, education and industrial applications.
Calculate and view detailed properties of chemical elements using their atomic symbols.
Convert between different units of measurement including length, mass, volume, temperature, pressure, and energy. Supports common scientific and engineering units.
Calculate pH values from H+ concentration, pOH, or acid/base solutions. Includes visual pH scale and detailed results.
Balance formula-based chemical equations with exact integer coefficients and automatic atom-conservation validation.
Calculate Arrhenius rate constants and integrated rate-law half-lives from user-supplied kinetic parameters.
Calculate Gibbs energy from user-supplied enthalpy, entropy, temperature, and optional constant heat capacity.
Explore phase states for supported pure substances using sourced critical points, triple points, and vapor-pressure correlations.
Draw, edit, and convert chemical structures. Supports multiple formats including SMILES, MOL, InChI, and image export. Features structure recognition from images.
Convert between different chemical structure formats including SMILES, InChI, IUPAC, MOL file, and 2D structure images.
Compare chemical structures and calculate similarity scores using different fingerprint methods and similarity metrics.
Generate and visualize 3D molecular conformations from SMILES notation. This tool helps you explore different possible 3D arrangements of your molecules.
Calculate required amounts of solute and solvent for preparing solutions of specific concentrations. Supports molarity, molality, mass percentage, and PPM.
Calculate chemical properties including density, molarity, molecular weight, and more. Get instant results for your chemical calculations.
Look up reference chemical properties and hazard information by name or CAS number. This summary is not a substitute for a supplier-issued SDS.
Calculate and visualize molecular descriptors including molecular weight, LogP, TPSA, and other important properties for chemical compounds