Chemfig Studio

draw a structure → get the LaTeX

Skeletal

Tool

Atom

Bond order

Charge · select an atom

Rings

Groups

Drawing carbon · single bonds

Draw like you would on paper

Click to drop an atom. Drag from one atom to the next to grow a bond. Double-click a vertex to sprout. Click a bond to toggle single / double / triple. Scroll to zoom; use the Move tool and drag the background to pan.

Output

chemfig source

LaTeX scale

Atoms

Bonds

Rings

Add \usepackage{chemfig} to your preamble. Drop the line above anywhere in the document body.

Drawing shortcuts

Click empty — place the active atom (and select it)
Click an atom — select it (groups & charge act on the selection)
Drag atom → empty — new bonded atom (snaps to 30°)
Drag atom → atom — bond two existing atoms
Double-click atom — sprout a new bond
Click a bond — cycle single → double → triple
Custom label — type any group (e.g. SO_3H), Set, then place or click an atom
Charge — select an atom, pick 2−/−/+/2+
Scroll zoom · Move tool + drag background pan · Fit reframes
Ctrl+Z undo · Del erase tool