Free Lewis Dot Structure Generator
Draw electron dot diagrams from a molecule name or formula
Type any molecule, ion, or compound and AI generates a clean, labeled Lewis dot structure showing all bonding pairs, lone pairs, and formal charges — ready for chemistry homework, lab reports, and exam prep.
Lewis dot structure examples
Click any example to load its prompt, or use it as a starting point for your own electron dot diagram.
What does this Lewis dot structure generator do?
It converts a molecule name, formula, or description into a clean, labeled Lewis dot structure — the electron diagram chemists use to show how atoms in a molecule are bonded and where lone pairs of electrons reside. You specify the molecule and any details (charge, resonance, expanded octet), and the AI draws the structure with bond lines, electron dots, and formal charge labels, giving you a publication-quality figure without manual dot counting.
Why use a Lewis dot structure maker
- Lewis structures are a foundational skill in general and organic chemistry — students draw them constantly for homework, quizzes, and exams.
- Counting electrons, placing lone pairs, and calculating formal charges by hand is error-prone and slow, especially for complex ions.
- A clean electron dot diagram makes bonding, lone pairs, and molecular geometry intuitive at a glance.
- Researchers and instructors need quick, accurate structures for lecture slides, textbook figures, and papers.
- Regenerating a diagram from text is far faster than re-drawing dots and lines every time the formula changes.
How to draw a Lewis dot structure
Count the total valence electrons for all atoms in the molecule, adding or subtracting for any net charge. Place the least electronegative atom in the center, then connect atoms with single bonds. Distribute remaining electrons as lone pairs to satisfy the octet rule (or duet for hydrogen). Convert lone pairs to multiple bonds where needed to minimize formal charges. For polyatomic ions, draw all resonance structures if electrons are delocalized. Describe this to the generator and refine until every atom satisfies the octet rule and formal charges are minimized.
Parts of a Lewis dot structure
- Bonding pairs — pairs of electrons (shown as lines or two dots) shared between two atoms forming a covalent bond.
- Lone pairs — non-bonding electron pairs sitting on a single atom, shown as two dots.
- Single, double, and triple bonds — one, two, or three shared electron pairs between atoms.
- Formal charges — the hypothetical charge on an atom assuming equal sharing; shown as +/− next to the atom symbol.
- Octet rule — the guiding principle that main-group atoms tend to surround themselves with 8 valence electrons.
- Resonance structures — two or more equivalent Lewis structures for the same molecule when electrons are delocalized.
Lewis Dot Structure Generator FAQ
What is a Lewis dot structure?
A Lewis dot structure (also called an electron dot diagram) is a 2-D representation of a molecule that shows every valence electron as either a bonding pair (a line between atoms) or a lone pair (two dots on one atom). It reveals how atoms are connected and where non-bonding electrons sit.
How do I find the number of valence electrons for a molecule?
Sum the valence electrons of every atom in the formula (using the group number for main-group elements). Add one electron per negative charge and subtract one per positive charge. This total is the number of dots you must distribute in the Lewis structure.
What is formal charge and why does it matter?
Formal charge equals (valence electrons of the free atom) − (lone pair electrons) − ½(bonding electrons). The best Lewis structure minimizes formal charges and places any negative formal charge on the more electronegative atom. Describe the formula to the generator and it will choose the structure with the lowest formal charges.
Can I draw resonance structures?
Yes — mention 'show all resonance structures' in your prompt (e.g. for NO₃⁻, CO₃²⁻, or benzene). The generator will draw each equivalent structure and indicate the delocalized bonding.
Is it suitable for high school or AP Chemistry assignments?
Yes. The diagrams are clean and labeled, suitable for homework, lab reports, and study guides. Always verify electron counts against your textbook rules before submitting.
Is it free?
Each generation uses a small number of credits. New accounts receive free credits, so you can draw Lewis dot structures without a subscription.
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