Work through 12 chemistry and physics calculators — molar mass, equation balancing, stoichiometry, pH, gas laws and more — built on IUPAC atomic-weight data and tested calculation engines.
The weighted average of isotope masses — the number on the periodic table.
Balance any chemical equation, including ionic and redox equations, and check the atom count on both sides.
Solve C1V1 = C2V2 for whichever value you leave blank, with the dilution factor.
Turn percent composition into an empirical formula, and into a molecular formula with the molar mass.
Solve PV = nRT for pressure, volume, moles or temperature, with unit conversion.
Calculate the molar mass of any chemical formula, with the mass each element contributes and the percent composition.
Convert between moles, grams and number of particles for any chemical formula.
Find the percent by mass of every element in a compound.
Convert between pH, pOH, hydrogen and hydroxide ion concentration, plus buffer pH.
The subatomic particle count for any element, isotope or ion.
Solve q = mcDeltaT for heat, mass, specific heat capacity or temperature change.
Balance a reaction, find the limiting reactant, and get the theoretical and percent yield.
These 12 science calculators run on tested engines: a chemical formula parser that handles hydrates, nested groups and ionic charges, an exact-fraction equation balancer, and atomic masses taken from the IUPAC/CIAAW dataset that also powers our interactive periodic table.
Most-used calculations: • Molar mass of any formula (and 120+ common compounds) • Balancing chemical equations, including ionic and redox • Stoichiometry: moles, limiting reactant, percent yield • Solution chemistry: molarity, dilution, pH • Gas laws and calorimetry
Tips for accurate science calculations: 1. Enter formulas with correct capitalization (Co is cobalt, CO is carbon monoxide) 2. Use parentheses for polyatomic groups, e.g. Ca(OH)2 3. Hydrates work with a dot or asterisk: CuSO4·5H2O 4. Check significant figures against your data 5. Cross-reference element data on our periodic table pages
This comprehensive guide is regularly updated to ensure accuracy. Last reviewed: 9/11/2026
From the IUPAC/CIAAW standard atomic weights (2021 revision, with the 2024 updates). All science calculators and the periodic table read from the same dataset, so values never disagree between tools.
Yes. The balancer treats charge as an additional conservation constraint, so net ionic and redox equations balance in one step, using exact fractions rather than floating-point approximations.
Write it as CuSO4·5H2O — a plain dot (.) or asterisk (*) also works. The parser understands hydrate notation, nested parentheses, and pasted unicode subscripts.
Yes. They are designed for chemistry students: molar mass results show per-element breakdowns, and the stoichiometry tools walk through moles, limiting reactant, and yield step by step.
Every element has its own page — atomic mass, electron configuration, valence electrons, common charges, discovery and uses — linked from the interactive periodic table.