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Zeanium Molecule Drawer
A free browser editor for drawing molecular structures, reaction schemes, and chemical figures with vector export.
Free. 32 of 65 checklist features confirmed.
Official demo
Main canvas
Canvas switches; surrounding interface stays dark.
Default drawings
Caffeine
Paclitaxel
Cholesterol in 3D
- No numbered version appeared; the served editor bundle identifies the build.
- Default style was Adv. Synth. Catal. with colored heteroatoms.
- Paclitaxel layout contains overlapping bonds and labels.
- The import dialog says SMILES stereochemistry is not imported.
- The default 3D preview spins and shows hydrogens and lone pairs.
Facts
- Version we tested
- Hosted, 5 Nov 2026
- Runs on
- Browser
- License
- Free browser access; no published software license identified.
- Price
- Free
- Relies on
- Not established. Public materials do not establish canvas provenance or chemistry dependencies.
- Draws with
- SVG for 2D drawing and export; HTML canvas for PNG; Three.js/WebGL for 3D.
- Chemistry from
- Custom JavaScript chemistry routines
- Interface
- React
- Main language
- JavaScript
- Other languages
- Source languages not publicly stated; generated JavaScript excluded.
- Renderer
- Original: In-house SVG renderer
- Third-party licenses
- Identified browser components: React and Three.js (MIT), Lucide icons (ISC), and Inter/Orbitron fonts (SIL OFL-1.1: redistributed fonts and derivatives retain OFL).
- SMILES interchange omits stereochemistry and isotope information.
- MOL support is V2000 only; text and arrows require .zeandraw files.
- Offline operation is unverified; resource caching requires a prior online visit.
In use
Screenshots from our test of this version.
Single, double and triple bonds
Single-bond tool instructions describe cycling through bond orders.
Ring tools
Ring tools include aromatic and several other ring shapes.
Chair and Haworth rings
A chair-shaped ring tool appears in the ring toolbar.
Reaction arrows
Forward and equilibrium arrows on the drawing canvas.
Curved mechanism arrows
A curved electron arrow starts from a bond.
Structure checking
The structure check flags ten items to review.
Formula and mass
Caffeine drawing with molecular formula and mass displayed below.
3D model view
Ball-and-stick 3D model of the molecule.
High-resolution PNG
Exported PNG image of a molecular drawing.
Features
- Tested by running it
- Seen in the app
- The manual says yes
- Partly, with the reason shown
- Not supported
- Not established, which is not the same as no
Select a mark for its proof. A filled mark opens our screenshot, or the manual if the check left nothing to picture. A ring opens the manual.
Drawing structures
- Yes, tested by running it: Drew single bond and cycled through double and triple. Opens the screenshot.Single, double and triple bondsDrew single bond and cycled through double and triple.zeanium.net
- Yes, tested by running it: Drew solid wedge, hashed wedge and wavy bond. Opens the cited page.Wedge, hash and wavy bondsDrew solid wedge, hashed wedge and wavy bond.zeanium.net
- No: Bond model supports orders 1–3 and graphical styles, without dative bonds. Opens the cited page.Dative, hydrogen and quadruple bondsBond model supports orders 1–3 and graphical styles, without dative bonds.zeanium.net
- Not establishedChoose double-bond side
- Yes, tested by running it: Placed benzene; multiple other ring tools are visible. Opens the screenshot.Ring toolsPlaced benzene; multiple other ring tools are visible.zeanium.net
- Yes, according to the manual: Two cyclohexane chair templates. Opens the cited page.Chair and Haworth ringsTwo cyclohexane chair templates.zeanium.net
- Yes, according to the manual: Drag to grow a zigzag carbon chain. Opens the cited page.Chain toolDrag to grow a zigzag carbon chain.zeanium.net
- Yes, tested by running it: VSEPR library placed boron trifluoride. Opens the cited page.Template libraryVSEPR library placed boron trifluoride.zeanium.net
- Not establishedSave your own templates
- Yes, according to the manual: Ph, Boc, OMe and other abbreviations expand into molecular graphs. Opens the cited page.Group abbreviationsPh, Boc, OMe and other abbreviations expand into molecular graphs.zeanium.net
- Partly: Element labels and charges supported; isotope metadata is not represented. Opens the cited page.Charges, isotopes and atom labelsElement labels and charges supported; isotope metadata is not represented.zeanium.net
- Yes, according to the manual: Automatic and manually positioned lone pairs. Opens the cited page.Radicals and lone pairsAutomatic and manually positioned lone pairs.zeanium.net
- Yes, according to the manual: Hover atoms to change elements; 1/2/3 set hovered bond order. Opens the cited page.Keyboard drawingHover atoms to change elements; 1/2/3 set hovered bond order.zeanium.net
- Partly: Lasso, rotation, and flips; no selected-structure resizing. Opens the cited page.Lasso select and transformsLasso, rotation, and flips; no selected-structure resizing.zeanium.net
- Not establishedTilt drawings in perspective
Reactions and mechanisms
- Yes, tested by running it: Drew forward and equilibrium arrows. Opens the screenshot.Reaction arrowsDrew forward and equilibrium arrows.zeanium.net
- Yes, tested by running it: Drew curved electron arrow from bond to atom. Opens the screenshot.Curved mechanism arrowsDrew curved electron arrow from bond to atom.zeanium.net
- Not establishedMachine-readable reactions
- Not establishedAtom mapping
- Yes, according to the manual: Chemical-symbol pickers include ‡, charges, radical dots, Δ, and hν. Opens the cited page.Orbitals and symbolsChemical-symbol pickers include ‡, charges, radical dots, Δ, and hν.zeanium.net
Figures and layout
- Partly: Plain multiline captions use preset fonts; no rich-text formatting. Opens the cited page.Rich text captionsPlain multiline captions use preset fonts; no rich-text formatting.zeanium.net
- Yes, according to the manual: Resizable brackets and editable freehand curves. Opens the cited page.Shapes, brackets and curvesResizable brackets and editable freehand curves.zeanium.net
- Yes, according to the manual: Line up selected molecules and symbols; distribute gaps evenly. Opens the cited page.Align and distributeLine up selected molecules and symbols; distribute gaps evenly.zeanium.net
- Not establishedGroup and ungroup
- Yes, according to the manual: Repositions chains and branches; rings remain fixed. Opens the cited page.2D structure cleanupRepositions chains and branches; rings remain fixed.zeanium.net
- Yes, according to the manual: ACS 1996, RSC, Wiley, and other journal presets. Opens the cited page.Journal drawing stylesACS 1996, RSC, Wiley, and other journal presets.zeanium.net
- Not establishedReusable custom styles
- Yes, according to the manual: Mechanism and freehand arrows have individual color controls. Opens the cited page.Color controlMechanism and freehand arrows have individual color controls.zeanium.net
- Partly: Selection backgrounds only; stripped from SVG and PNG exports. Opens the cited page.Color highlightingSelection backgrounds only; stripped from SVG and PNG exports.zeanium.net
- Not establishedPage layout and multipage
- Not establishedImported pictures
- Not establishedTLC plates and tables
Chemistry intelligence
- Yes, according to the manual: Flags excess valence, overlapping atoms, and undefined stereocenters. Opens the cited page.Structure checkingFlags excess valence, overlapping atoms, and undefined stereocenters.zeanium.net
- Yes, according to the manual: Computes R/S centers and E/Z double-bond descriptors. Opens the cited page.R/S and E/Z labelsComputes R/S centers and E/Z double-bond descriptors.zeanium.net
- Yes, tested by running it: Caffeine displayed C8H10N4O2 and 194.19 g/mol. Opens the screenshot.Formula and massCaffeine displayed C8H10N4O2 and 194.19 g/mol.zeanium.net
- Yes, tested by running it: Properties dialog displayed estimated logP and TPSA. Opens the cited page.Property estimatesProperties dialog displayed estimated logP and TPSA.zeanium.net
- Yes, tested by running it: PubChem search for aspirin produced a structure. Opens the cited page.Name to structurePubChem search for aspirin produced a structure.zeanium.net
- No: Action search found name lookup only, not structure naming. Opens the cited page.Structure to nameAction search found name lookup only, not structure naming.
- Not establishedNMR prediction
- Not establishedR-groups and query structures
- Not establishedPolymers and repeat units
- Not establishedPeptides and nucleic acids
- Not establishedImage to structure
- Yes, tested by running it: PubChem aspirin lookup returned a structure. Opens the cited page.Online structure lookupPubChem aspirin lookup returned a structure.zeanium.net
- Yes, tested by running it: Cholesterol model built automatically and rotated in depth. Opens the screenshot.3D model viewCholesterol model built automatically and rotated in depth.zeanium.net
- Not establishedCrystal structures
Files and exchange
- No: Selected CDXML; drawing stayed unchanged; no export option. Opens the cited page.CDXML import and exportSelected CDXML; drawing stayed unchanged; no export option.
- Not establishedCDX import and export
- Partly: MOL import/export and single SDF import worked; no SDF export. Opens the cited page.MOL and SDFMOL import/export and single SDF import worked; no SDF export.zeanium.net
- Partly: Read and copied SMILES; importer discards stereochemistry. Opens the cited page.SMILESRead and copied SMILES; importer discards stereochemistry.zeanium.net
- Not establishedInChI
- Not establishedRXN files
- Yes, tested by running it: Exported SVG files for all three fixtures. Opens the cited page.SVG exportExported SVG files for all three fixtures.zeanium.net
- No: File menu and action search offered no PDF export. Opens the cited page.PDF exportFile menu and action search offered no PDF export.
- Partly: PNG exported at 2000 pixels wide; no DPI control shown. Opens the screenshot.High-resolution PNGPNG exported at 2000 pixels wide; no DPI control shown.zeanium.net
- Not establishedPaste to and from ChemDraw
- Not establishedEditable in Word or PowerPoint
- Not establishedWindows Office OLE
APIs and automation
- Not establishedPython API
- Not establishedJavaScript or TypeScript API
- Not establishedCommand-line tool
- Not establishedAI agent control
- Not establishedBuilt-in AI assistant
Embedding and extension
- Not establishedPlugins
- No: Hosted editor blocks framing; no documented SDK found. Opens the cited page.Embed in your own appHosted editor blocks framing; no documented SDK found.zeanium.net