This website is biased toward ReShiki, because its maintainer also maintains ReShiki. Please be careful.
Butlerov
An embeddable 2D chemical structure editor for drawing molecules in web applications.
Open source. 18 of 65 checklist features confirmed.
Main canvas
SMILES import overlaps and loses stereochemistry.
Default drawings
- CodePen returned a Cloudflare verification page in headless Chromium.
- Local adapter used core package 0.1.6; buttons expose its API.
- SMILES caffeine became C8H14N4O2 instead of C8H10N4O2.
- MOL round trips preserved both fixtures' isomeric structures.
- Down bonds display hollow wedges rather than hashed wedges.
- Current Kekule caffeine SMILES preserves connectivity but produces an overlapping layout.
- Current Kekule paclitaxel SMILES retains connectivity but loses stereochemistry.
- Hosted demo canvas paste did not load either SMILES; its MOL text box has no load button.
- New captures use the earlier local adapter; its core bundle matches the hosted demo bundle byte-for-byte.
Facts
- GitHub stars
- 13 stars on 6 Nov 2026
- First commit
- 20 Jun 2022
- Repository activity
- 151 commits, 7 contributors, last push 3 Apr 2026
- Latest version
- vue-0.1.7
- Version we tested
- 0.1.6
- Runs on
- Browser
- License
- MIT license permits commercial and noncommercial use.
- Price
- Free
- Relies on
- No third-party engine found. In-house molecular graph, SMILES parser, mass calculations, and chemical drawing.
- Draws with
- Konva.js on HTML canvas
- Chemistry from
- In-house TypeScript molecular graph, converters and formula/mass calculations
- Interface
- Konva controls; Vue 3 wrapper; Electron desktop shell
- Main language
- TypeScript
- Other languages
- None
- Renderer
- Original: Butlerov bond and label drawing (Konva)
- Third-party licenses
- MIT (Konva/Vue/Vuetify); Apache-2.0 (MDI icon fonts in desktop app).
- Single-structure canvas; documented multi-object scheme mode is not implemented.
- SMILES export is unimplemented despite documentation showing converter-based serialization.
- Documentation lists V3000/SDF; converter implements V2000 and reads only the first SDF record.
In use
Screenshots from our test of this version.

Single, double and triple bonds
Bond menu lists single, double, and triple options.

Wedge, hash and wavy bonds
Molecule with solid and hollow wedge bonds.

Ring tools
Ring menu lists phenyl and cycloalkane sizes.

Chain tool
Atom menu includes an Add normal chain option.

Charges, isotopes and atom labels
Atom menu includes Edit and Isotopes options.

Keyboard drawing
Bond menu displays keyboard shortcuts for bond types.

SMILES
Loaded SMILES appears above an overlapping 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: Changed a bond to single, double, and triple. Opens the screenshot.Single, double and triple bondsChanged a bond to single, double, and triple.github.com
- Partly: Solid, hollow down wedge and wavy; no hashed wedge. Opens the screenshot.Wedge, hash and wavy bondsSolid, hollow down wedge and wavy; no hashed wedge.github.com
- Not establishedDative, hydrogen and quadruple bonds
- Yes, according to the manual. Opens the cited page.Choose double-bond sidegithub.com
- Yes, tested by running it: Created cyclohexane and phenyl using context menus. Opens the screenshot.Ring toolsCreated cyclohexane and phenyl using context menus.github.com
- Not establishedChair and Haworth rings
- Partly: Menu adds chosen chain length; no drag tool observed. Opens the screenshot.Chain toolMenu adds chosen chain length; no drag tool observed.github.com
- No: No library beyond rings found in inspected menus. Opens the cited page.Template libraryNo library beyond rings found in inspected menus.
- Not establishedSave your own templates
- Yes, according to the manual: Recognizes abbreviation tokens and expands them into molecular graphs. Opens the cited page.Group abbreviationsRecognizes abbreviation tokens and expands them into molecular graphs.github.com
- Yes, according to the manual: Element/custom labels, charge shortcuts and isotope selection. Opens the cited page.Charges, isotopes and atom labelsElement/custom labels, charge shortcuts and isotope selection.github.com
- Not establishedRadicals and lone pairs
- Yes, tested by running it: Keyboard shortcuts changed bond orders and inserted rings. Opens the screenshot.Keyboard drawingKeyboard shortcuts changed bond orders and inserted rings.github.com
- Partly: Selection limited to connected components, chains, rings and molecular fragments. Opens the cited page.Lasso select and transformsSelection limited to connected components, chains, rings and molecular fragments.github.com
- Not establishedTilt drawings in perspective
Reactions and mechanisms
- No: No arrow command found in inspected editor menus. Opens the cited page.Reaction arrowsNo arrow command found in inspected editor menus.
- No: No curved-arrow command found in inspected menus. Opens the cited page.Curved mechanism arrowsNo curved-arrow command found in inspected menus.
- Not establishedMachine-readable reactions
- Not establishedAtom mapping
- Not establishedOrbitals and symbols
Figures and layout
- Not establishedRich text captions
- Not establishedShapes, brackets and curves
- Not establishedAlign and distribute
- Not establishedGroup and ungroup
- Partly: Local automatic geometry adjustments and symmetry tools only. Opens the cited page.2D structure cleanupLocal automatic geometry adjustments and symmetry tools only.github.com
- Not establishedJournal drawing styles
- Partly: Reusable API styles; editor document serialization omits bond/font styles. Opens the cited page.Reusable custom stylesReusable API styles; editor document serialization omits bond/font styles.github.com
- Partly: Shared theme sets atom and bond colors, not individual objects. Opens the cited page.Color controlShared theme sets atom and bond colors, not individual objects.github.com
- Yes, according to the manual: Configurable colored underlays highlight selected atoms and bonds in widget. Opens the cited page.Color highlightingConfigurable colored underlays highlight selected atoms and bonds in widget.github.com
- Not establishedPage layout and multipage
- Not establishedImported pictures
- Not establishedTLC plates and tables
Chemistry intelligence
- Not establishedStructure checking
- Not establishedR/S and E/Z labels
- Yes, tested by running it: Adapter displayed formula and molecular weight from editor API. Opens the cited page.Formula and massAdapter displayed formula and molecular weight from editor API.github.com
- Not establishedProperty estimates
- No: No name conversion command found in inspected menus. Opens the cited page.Name to structureNo name conversion command found in inspected menus.
- No: No naming command found in inspected menus. Opens the cited page.Structure to nameNo naming command found in inspected menus.
- Not establishedNMR prediction
- Not establishedR-groups and query structures
- Not establishedPolymers and repeat units
- Not establishedPeptides and nucleic acids
- Not establishedImage to structure
- Not establishedOnline structure lookup
- No: No 3D view command found in inspected menus. Opens the cited page.3D model viewNo 3D view command found in inspected menus.
- Not establishedCrystal structures
Files and exchange
- No: No CDXML command found in inspected menus. Opens the cited page.CDXML import and exportNo CDXML command found in inspected menus.
- Not establishedCDX import and export
- Yes, tested by running it: Adapter read and wrote MOL; one SDF record loaded. Opens the cited page.MOL and SDFAdapter read and wrote MOL; one SDF record loaded.github.com
- Partly: Import corrupted both fixtures; SMILES export reports unimplemented. Opens the screenshot.SMILESImport corrupted both fixtures; SMILES export reports unimplemented.github.com
- Not establishedInChI
- Not establishedRXN files
- No: No SVG export command found in inspected menus. Opens the cited page.SVG exportNo SVG export command found in inspected menus.
- No: No PDF export command found in inspected menus. Opens the cited page.PDF exportNo PDF export command found in inspected menus.
- No: No PNG export command found in inspected menus. Opens the cited page.High-resolution PNGNo PNG export command found in inspected menus.
- Not establishedPaste to and from ChemDraw
- Not establishedEditable in Word or PowerPoint
- Not establishedWindows Office OLE
APIs and automation
- Not establishedPython API
- Yes, according to the manual. Opens the cited page.JavaScript or TypeScript APIgithub.com
- Not establishedCommand-line tool
- Not establishedAI agent control
- Not establishedBuilt-in AI assistant
Embedding and extension
- Not establishedPlugins
- Yes, according to the manual: Instantiate MoleculeEditor with a div stage; npm or UMD script. Opens the cited page.Embed in your own appInstantiate MoleculeEditor with a div stage; npm or UMD script.github.com


