Free chemistry tools for lab and production work.
Calculators and lookups for everyday chemistry — molar mass, dilutions, pH, NFPA, the periodic table, and 75 more. No login, no paywall.
99 / Why these tools
How they work01 Runs in your browser
The calculators do their work locally, with no server round-trip. Type a value and the answer updates as you go.
02 Shows its working
Each tool spells out the formula it uses — Henderson-Hasselbalch, Beer-Lambert, Arrhenius and the rest — with sources, so you can check the result.
03 Covers the safety side
NFPA diamonds, GHS labels, exposure limits and compatibility checks are here too — with a clear note that they don't replace an official SDS.
04 Print & share
NFPA diamonds, GHS labels and prep cards are all printable. Hand the page to your team or pin it on the cabinet.
Frequently asked questions
Are the MoldChem chemistry calculators free?
Yes. All 80 chemistry calculators and lookups are free to use, with no login, no paywall, and no usage limits.
Do I need an account or any download to use the tools?
No. Every tool runs in your web browser — nothing to install and no sign-up required.
Do the calculators work offline and keep my data private?
Yes. Calculations run locally in your browser, so once a page has loaded it works without a connection. Only the chemical-name and CAS lookups query public databases (PubChem, NCI/CADD, OPSIN) through a keyless proxy.
How accurate are the chemistry calculators?
Each tool shows the formula it uses and its data sources (for example IUPAC 2021 atomic weights and NIST buffer pKa values), so you can check every result. Treat them as planning and cross-checking aids, and verify safety-critical figures against primary sources or the SDS.
Who makes MoldChem Tools?
MoldChem Tools is built and maintained by the MoldChem team, and offered free for labs, shop floors, and students — no account, no paywall.