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Chemifree
An early-stage chemical drawing workspace for local structure editing, inspection and limited chemical file conversion.
Open source. 22 of 65 checklist features confirmed.
Main canvas
Canvas and interface both change.
Default drawings
Caffeine
Paclitaxel
No 3D view
Cholesterol in 3D
- SMILES imports use an input-order grid without chemical layout.
- Bonds cross and labels overlap in both SMILES drawings.
- Paclitaxel stores 11 stereo configurations without drawing wedges.
- The default canvas uses a dark background and light bonds.
- Image evidence uses canvas crops because scene export is unimplemented.
Facts
- GitHub stars
- 0 stars on 6 Nov 2026
- First commit
- 26 Oct 2026
- Repository activity
- 557 commits, 1 contributor, last push 5 Nov 2026
- Version we tested
- 0.1.0
- Runs on
- Browser
- License
- MIT license; free to use, modify and redistribute.
- Price
- Free
- Relies on
- No third-party engine found. Custom SVG canvas and in-house Rust chemistry.
- Draws with
- SVG in the browser; scene/file rendering export is unimplemented.
- Chemistry from
- In-house Rust models for bounded valence, aromaticity, identity, stereochemistry and formula/mass calculations.
- Interface
- React and TypeScript with shadcn/ui (Base UI), Tailwind CSS and Vite.
- Main language
- TypeScript
- Other languages
- Rust: Chemistry, codecs and local API
- Renderer
- Original: Chemifree SVG DrawingLayer
- Third-party licenses
- MIT/ISC UI components and icons; OFL-1.1 font (Geist).
- Download
- 2.7 MB
- Installed
- 116 MB
- Early-stage source build; no tagged release, installer or hosted editor.
- One graph and page; captions and SVG/PDF/PNG scene export are unimplemented.
- CDXML/CDX imports have explicit losses; edited drawings cannot be exported to these formats.
In use
Screenshots from our test of this version.
Single, double and triple bonds
Bond toolbar and structure with single and double bonds.
Wedge, hash and wavy bonds
Stereo bond tools and a wavy bond on the canvas.
Reaction arrows
A forward arrow beside a structure on the canvas.
Shapes, brackets and curves
A forward arrow beside a structure on the canvas.
R/S and E/Z labels
Stereo panel with atom and bond label switches.
MOL and SDF
MOL and SDF controls show a rejected 3D SDF import.
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: Created a bond and cycled single, double and triple orders. Opens the screenshot.Single, double and triple bondsCreated a bond and cycled single, double and triple orders.github.com
- Yes, tested by running it: Applied solid wedge, hashed wedge and wavy marks. Opens the screenshot.Wedge, hash and wavy bondsApplied solid wedge, hashed wedge and wavy marks.github.com
- Partly: Dative available; no hydrogen or quadruple bond tools. Opens the cited page.Dative, hydrogen and quadruple bondsDative available; no hydrogen or quadruple bond tools.github.com
- Not establishedChoose double-bond side
- No: Dedicated ring insertion remains planned. Opens the cited page.Ring toolsDedicated ring insertion remains planned.github.com
- Not establishedChair and Haworth rings
- Not establishedChain tool
- No: Structure and substituent template insertion remains planned. Opens the cited page.Template libraryStructure and substituent template insertion remains planned.github.com
- No: User templates remain planned. Opens the cited page.Save your own templatesUser templates remain planned.github.com
- No: Abbreviation collapse and expansion remain planned. Opens the cited page.Group abbreviationsAbbreviation collapse and expansion remain planned.github.com
- Yes, according to the manual: Element labels, charges and isotope mass numbers are editable. Opens the cited page.Charges, isotopes and atom labelsElement labels, charges and isotope mass numbers are editable.github.com
- Yes, according to the manual: Editable radical states render as dots or rings. Opens the cited page.Radicals and lone pairsEditable radical states render as dots or rings.github.com
- Not establishedKeyboard drawing
- Partly: Marquee selection and movement; rotation, flip and resize unavailable. Opens the cited page.Lasso select and transformsMarquee selection and movement; rotation, flip and resize unavailable.github.com
- No: 3D coordinates and projected scene geometry remain planned. Opens the cited page.Tilt drawings in perspective3D coordinates and projected scene geometry remain planned.github.com
Reactions and mechanisms
- Partly: Inserted forward arrow; no alternate arrow types shown. Opens the screenshot.Reaction arrowsInserted forward arrow; no alternate arrow types shown.github.com
- No: Electron-pushing arrows remain planned. Opens the cited page.Curved mechanism arrowsElectron-pushing arrows remain planned.github.com
- No: Chemical reaction documents remain unimplemented. Opens the cited page.Machine-readable reactionsChemical reaction documents remain unimplemented.github.com
- No: Reaction atom mapping remains planned. Opens the cited page.Atom mappingReaction atom mapping remains planned.github.com
- No: Orbital and scientific-symbol scene types remain planned. Opens the cited page.Orbitals and symbolsOrbital and scientific-symbol scene types remain planned.github.com
Figures and layout
- No: Free-text captions remain unimplemented. Opens the cited page.Rich text captionsFree-text captions remain unimplemented.github.com
- Partly: Forward arrow inserted; line and rectangle commands present. Opens the screenshot.Shapes, brackets and curvesForward arrow inserted; line and rectangle commands present.github.com
- No: Alignment and distribution remain planned. Opens the cited page.Align and distributeAlignment and distribution remain planned.github.com
- Yes, according to the manual: Group, ungroup and move scene objects together. Opens the cited page.Group and ungroupGroup, ungroup and move scene objects together.github.com
- No: CLI layout.structure reports operation_not_implemented. Opens the cited page.2D structure cleanupCLI layout.structure reports operation_not_implemented.github.com
- Not establishedJournal drawing styles
- Yes, according to the manual: Save document styles; import settings or reuse new-document defaults. Opens the cited page.Reusable custom stylesSave document styles; import settings or reuse new-document defaults.github.com
- Not establishedColor control
- Partly: Selection and hover backgrounds only; scene export is unimplemented. Opens the cited page.Color highlightingSelection and hover backgrounds only; scene export is unimplemented.github.com
- No: One page; multipage documents unimplemented. Opens the cited page.Page layout and multipageOne page; multipage documents unimplemented.github.com
- No: Image scene objects remain planned. Opens the cited page.Imported picturesImage scene objects remain planned.github.com
- No: Tables, TLC plates and gels remain planned. Opens the cited page.TLC plates and tablesTables, TLC plates and gels remain planned.github.com
Chemistry intelligence
- Yes, according to the manual: Bounded valence model flags invalid and unsupported atom states. Opens the cited page.Structure checkingBounded valence model flags invalid and unsupported atom states.github.com
- Partly: Labels stored configurations; CIP Rules 4a–5 and pseudoasymmetry unsupported. Opens the cited page.R/S and E/Z labelsLabels stored configurations; CIP Rules 4a–5 and pseudoasymmetry unsupported.github.com
- Partly: Formula works; mass refused without compatible external dataset. Opens the cited page.Formula and massFormula works; mass refused without compatible external dataset.github.com
- No: XLogP calculation remains planned. Opens the cited page.Property estimatesXLogP calculation remains planned.github.com
- No: CLI name parser reports operation_not_implemented. Opens the cited page.Name to structureCLI name parser reports operation_not_implemented.github.com
- No: CLI naming reports operation_not_implemented. Opens the cited page.Structure to nameCLI naming reports operation_not_implemented.github.com
- No: Proton and carbon NMR prediction remain planned. Opens the cited page.NMR predictionProton and carbon NMR prediction remain planned.github.com
- Yes, according to the manual: Element-list and generic query atoms; substructure matching supported. Opens the cited page.R-groups and query structuresElement-list and generic query atoms; substructure matching supported.github.com
- No: Polymer repeat-unit and SRU semantics remain planned. Opens the cited page.Polymers and repeat unitsPolymer repeat-unit and SRU semantics remain planned.github.com
- No: Biopolymer expansion unimplemented. Opens the cited page.Peptides and nucleic acidsBiopolymer expansion unimplemented.github.com
- Not establishedImage to structure
- Not establishedOnline structure lookup
- No: No 3D view; cholesterol SDF import refused. Opens the cited page.3D model viewNo 3D view; cholesterol SDF import refused.
- Not establishedCrystal structures
Files and exchange
- Partly: Exported and reimported caffeine; bounded profile reports losses. Opens the cited page.CDXML import and exportExported and reimported caffeine; bounded profile reports losses.github.com
- Partly: Bounded codec; edited drawings cannot be exported as CDX. Opens the cited page.CDX import and exportBounded codec; edited drawings cannot be exported as CDX.github.com
- Yes, tested by running it: 2D MOL import/export and SDF export work; cholesterol SDF refused. Opens the screenshot.MOL and SDF2D MOL import/export and SDF export work; cholesterol SDF refused.github.com
- Partly: Fixture imports and writes work; directional stereo is refused. Opens the cited page.SMILESFixture imports and writes work; directional stereo is refused.github.com
- No: InChI explicitly unimplemented. Opens the cited page.InChIInChI explicitly unimplemented.github.com
- No: Reaction CTfiles are unsupported. Opens the cited page.RXN filesReaction CTfiles are unsupported.github.com
- No: render.scene refuses SVG; no GUI image export command. Opens the cited page.SVG exportrender.scene refuses SVG; no GUI image export command.github.com
- No: render.scene refuses PDF; no GUI image export command. Opens the cited page.PDF exportrender.scene refuses PDF; no GUI image export command.github.com
- No: render.scene refuses PNG; no GUI image export command. Opens the cited page.High-resolution PNGrender.scene refuses PNG; no GUI image export command.github.com
- No: Chemical clipboard exchange remains planned. Opens the cited page.Paste to and from ChemDrawChemical clipboard exchange remains planned.github.com
- No: Desktop and host integration unimplemented. Opens the cited page.Editable in Word or PowerPointDesktop and host integration unimplemented.github.com
- Not establishedWindows Office OLE
APIs and automation
- Not establishedPython API
- Not establishedJavaScript or TypeScript API
- Yes, tested by running it: CLI version, capabilities and operation requests executed. Opens the cited page.Command-line toolCLI version, capabilities and operation requests executed.github.com
- Yes, according to the manual: Documented HTTP and JSON-lines operation interface for external agents. Opens the cited page.AI agent controlDocumented HTTP and JSON-lines operation interface for external agents.github.com
- Not establishedBuilt-in AI assistant
Embedding and extension
- Yes, according to the manual: Rust-only replacement of the CIP labeler through Application::with_cip_labeler. Opens the cited page.PluginsRust-only replacement of the CIP labeler through Application::with_cip_labeler.github.com
- Not established: Local web workspace; no supported editor embedding interface documented.Embed in your own appLocal web workspace; no supported editor embedding interface documented.github.com