Chemistry Formula Calculator
Calculate molar mass, empirical & molecular formulas, balance chemical equations, and percent composition. Built-in 118-element periodic table with atomic masses. Formula parser handles parentheses and hydrates (CuSO4·5H2O). Equation balancer uses brute-force integer search. 100% client-side — 18 extra features including CSV/text export, history, shareable URL, presets, isotope selector.
About Chemistry Formula Calculator
Calculate molar mass, empirical & molecular formulas, balance chemical equations, and percent composition. Built-in 118-element periodic table with atomic masses. Formula parser handles parentheses and hydrates (CuSO4·5H2O). Equation balancer uses brute-force integer search. 100% client-side — 18 extra features including CSV/text export, history, shareable URL, presets, isotope selector. Everything runs locally in your browser — your data never leaves your device.
How to use
- Enter your input in the tool above.
- Adjust any options to your preference.
- Use the Copy or Download buttons to save the result.
- Everything happens locally — your data never leaves your browser.
FAQ
How does the chemistry formula calculator work?
Pick a calculation type (molar mass, empirical formula, molecular formula, balance equation, or percent composition), enter a chemical formula like H2O or C6H12O6, and the tool parses it against the built-in 118-element periodic table. For empirical/molecular modes, paste experimental percent composition (element,percentage per line). For balance mode, type an equation like H2 + O2 = H2O.
Does the formula parser handle parentheses and hydrates?
Yes. The parser handles nested parentheses like (NH4)2SO4 and Fe2(SO4)3, and the hydrate dot notation like CuSO4·5H2O (use the middle-dot character · or '*' as separator). Hydrate segments with a leading coefficient are multiplied correctly.
How does the equation balancer work?
The balancer parses reactants and products, enumerates each element, then searches integer coefficients from 1 to 20 for every species until the law of conservation of mass is satisfied. It returns the smallest such set and renders the balanced equation.
What extra features does this tool have compared to others?
(1) 5 calculation types. (2) 118-element periodic table built-in. (3) Formula parser (parentheses + hydrates). (4) Molar mass calculator. (5) Empirical formula from % composition. (6) Molecular formula from empirical + molar mass. (7) Equation balancer (integer search). (8) Percent composition calculator. (9) Formula validator. (10) Text report renderer. (11) CSV renderer. (12) Copy + Download .txt + Download CSV. (13) History (localStorage, last 20). (14) Shareable URL. (15) Summary stats. (16) 10 common-compound presets. (17) Hydrate dot handler. (18) Common-isotope mass selector.
Is my data sent anywhere?
No. All calculations run locally in your browser. The periodic table is bundled in the page. History is stored in localStorage on this device only.
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