Molecular Weight Calculator - Free, Instant, In Your Browser
Enter a simple chemical formula (e.g. H2O, C6H12O6, NaCl) to calculate its molecular weight in g/mol.
How to use Molecular Weight Calculator
- 1Paste your text or data into the input box above.
- 2Molecular Weight Calculator runs instantly, right in your browser.
- 3Copy the result or use it directly.
Your file is processed in your browser and is never uploaded.
Frequently Asked Questions
What's the formula?
The molecular weight is the sum of each element's atomic mass, multiplied by how many atoms of it appear in the formula. Nested parentheses are not supported.
Is my data sent to a server?
No - everything runs entirely in your browser with JavaScript. Nothing is uploaded.