Draw molecules online, free – just describe them
Free AI chemical structure editor · no install · no account needed
MolChart is a free online molecule drawing tool that works differently from classic structure editors: instead of picking a bond tool and clicking atoms into place, you describe the molecule. The AI assistant draws it on the canvas, checks every valence, and compares the result with PubChem before it shows it to you. The classic way still works too – the drawing palette of elements, bonds and rings is one click away in the editor.
How to draw a molecule
- Open molchart.com – no sign-up needed.
- Type what you want in the assistant box, for example “draw ibuprofen”, “CC(=O)Oc1ccccc1C(=O)O” or “a benzene ring with a nitro group para to a methoxy group”, and press Enter.
- Refine it by instruction: “add a chlorine at position 4”, “make the double bond E”, “replace the ester with an amide”.
- Export from the File menu: PNG, SVG, SMILES or MOL.
Try these prompts
- draw caffeine
- draw aspirin and label the carboxylic acid
- draw L-alanine with correct stereochemistry
- draw glucose in the pyranose form
- draw the reaction of ethanol with acetic acid to give ethyl acetate
What you get
- Clean 2D structures with standard bond geometry, wedge/hash stereo bonds and implicit hydrogens.
- Verification: the assistant checks the drawn structure against PubChem for named compounds and reports valence errors.
- Analysis tools: IUPAC name, formula, molecular weight, stereocentres, PubChem lookup, 3D view.
- Reaction schemes with arrows and text.
Open the editor and draw caffeine →
Frequently asked questions
Do I need to install anything?
No. MolChart runs in any modern browser on desktop or mobile. There is no download and no account is needed to start.
Do I have to draw bonds by hand?
No. You type what you want – a name, a SMILES string, or a description such as “a cyclohexane ring with two hydroxyl groups cis to each other” – and the assistant draws it, then verifies the result. If you would rather draw it yourself, the palette of elements, bonds and ring templates is there as well.
Is it really free?
Yes. Drawing, editing, analysis and export are free in your browser with no account. A free account saves your documents, and a $10/month membership adds unlimited AI assistant use.
Can I download the drawing?
Yes – export PNG or SVG images for documents and slides, or SMILES and MOL files for other chemistry software.