Settings reference
Short answer: Click the gear button (Settings) to open the Settings window. It has eight sections: General, Style, Bonds, Style presets, AI, Plugins, Shortcuts and Touch screen. Changes save automatically, and each section has a Reset to defaults button.
Where to find it#
- Click the gear button (Settings). In the command palette, type "settings" and pick a section, such as Settings: Bonds.
- Pick a section in the left list. On a computer, type in Search at the top of the list to jump to a setting.
- Change a value. The footer shows Changes save automatically.
- To undo your changes in one section, click Reset to defaults, then click again to confirm.
Reset all settings… at the bottom of the list resets every section. It also asks for a second click. Settings live in this browser, on this device. See Privacy and storage.
The Previews switch in the General, Style and Bonds sections shows a small example structure under options that change the drawing. It is off by default.
General#
Appearance#
| Setting | What it does | Default |
|---|---|---|
| Language | Interface language. See Change the language. | Your browser language on the first visit, else English |
| Theme | Light, Elegant dark or Ink dark. Ink dark uses a black canvas with white bonds and atom letters. | Light |
| Layout | Scientific shows every button. Educational shows two compact rows and one tool column. See Themes and layouts. | Scientific |
| Toolbar icon size | Small, Medium, Large or Extra large. Buttons and gaps scale too. Computers only. | Small |
Atom labels#
| Setting | What it does | Default |
|---|---|---|
| Show explicit H labels | Draws hydrogens on carbons for display. It does not add real H atoms. | Off |
| Color atom labels by element | N blue, O red and so on. Colors you paint always apply. The 3D viewer always uses element colors. | Off |
| Color bonds to heteroatoms | Bonds to N, O and other heteroatoms take the label color. | Off |
| Condensed group labels | Terminal groups show labels such as CH₃ or NH₂. | Off |
| R/S and E/Z labels | Shows CIP labels on stereocenters and double bonds. | Off |
Drawing#
| Setting | What it does | Default |
|---|---|---|
| Auto-layout after bond burst | When you add several bonds quickly, MolDraw tidies that fragment, like Clean up. | On |
| Legacy accelerator for 2D layout | An older layout path that Clean up and SMILES to 2D can try for hard ring systems. Turn it off to use only the built-in layout. | On |
| Lone pair style | Dots or Line (a short bar) for new lone pairs. | Dots |
Teaching#
| Setting | What it does | Default |
|---|---|---|
| Structure display | Skeletal formula or Lewis structure. Only the view changes. | Skeletal formula |
| Free sketch mode | Relaxes chemistry rules. Five switches appear under it, all on: No automatic hydrogens, No valence correction, Allow any charge (up to ±9), Allow any number of lone pairs (up to four) and Allow any number of bonds. | Off |
| Show errors | Amber dot on atoms with too many bonds, amber ring on unclear wedge or dash stereo. Never exported. | On |
| Error tooltips | Hover or tap a marked atom to read the error. Shown when Show errors is on. | On |
| Preview the next atom | A faint bond and atom show where the next click adds an atom. | On in Scientific, off in Educational |
For teaching use, see Educational layout and Teaching menu.
Canvas#
| Setting | What it does | Default |
|---|---|---|
| Snap to grid | Dragged molecules and reaction arrows snap to the grid. Hold Shift to move freely. | Off |
| Show grid | Draws a light grid on the canvas. | Off |
| Canvas assistance guidelines | Alignment lines while you drag, and snap ticks while you draw bonds. | On |
| Snap curved arrows | Curved arrows attach to lone pairs, bonds and atoms and move with the structure. Hold Alt to place an end freely. | On |
Export#
| Setting | What it does | Default |
|---|---|---|
| Reaction component margin size | Space around reaction parts, 0 to 24 pt. | 1.6 pt |
| Image resolution | 1× (match font size), low (2×), medium (3×) or high (4×). Applies to white PNG, JPEG and PDF. Transparent PNG and SVG stay 1×. | high (4×) |
Style#
These change how structures look. The Style ribbon has the same controls. See Style and display.
| Setting | What it does | Default |
|---|---|---|
| Structure theme | Default (skeletal) or Ball and stick. Plugins can add more. | Default |
| Font | Font for atom labels, such as Times New Roman, Arial or Helvetica. | Times New Roman |
| Bold atom labels | Element and group labels in bold. | Off |
| Font size | Label size at zoom 1, 6 to 36 px. | 20 px |
| Sub font size | Subscript size, 6 to 36 px. | 16 px |
| Bond length | 24 to 80 px. | 45 px |
| Fixed bond length | New bonds snap to the bond length while you drag. Off lets you drag any length. | On |
| Bond spacing | Gap between double bond lines, 4 to 45 % of length. | 35 % |
| Bond thickness | 1 to 14 px. | 1.5 px |
| Stereo (Wedge) bond width | 2 to 24 px. | 10 px |
| Hash spacing | 0.5 to 14 px. | 3.5 px |
Bonds#
| Setting | What it does | Default |
|---|---|---|
| Fixed bond length | Same switch as in Style. | On |
| Bond angle snap | New bonds and rings snap to this angle, 5 to 45°. Use 15° for RSC style and 30° for ACS or Nature. | 30° |
Style presets#
One click sets bond and label values for a journal or for slides. Each card shows aspirin in that style. The presets are Balanced (screen), ACS 1996, ACS, large labels, Large (17 pt), RSC, Nature Portfolio, Nature Chemistry (classic) and Slides & posters. The default is Balanced (screen). For journal figures, see Publication-ready figures.
AI, Plugins and Shortcuts#
- AI sets the Chat provider (Gemini, Claude, OpenAI or DeepSeek), the Model and an API key for each provider. Gemini is the default. Keys stay in this browser. See AI providers and API keys. This section also has the Local session bridge for AI agents, off by default.
- Plugins lists every plugin with Install, Enable, Disable and Uninstall. You need to sign in to install plugins. See Plugins overview.
- Shortcuts lists every key. Click Edit, then press a new key. Esc cancels. Reset all shortcuts restores the defaults. See Keyboard shortcuts.
Touch screen#
| Setting | What it does | Default |
|---|---|---|
| One-finger pan on empty canvas | With the Select tool, one finger on empty canvas pans instead of drawing a selection box. | Off |
| Magnifier while drawing | A 2× loupe above your fingertip while you drag a bond, ring or chain. | On |
| Pointer debug overlay | Shows pen and touch details on the canvas. For testing devices. | Off |
See Phone and tablet for gestures.
Tips#
- On a phone, Settings opens full screen. Turn on Show descriptions at the top to read the help text under each option. Reset defaults sits at the bottom.
- If the canvas looks wrong after many changes, reset only the section you changed.
Questions and answers
How do I reset MolDraw settings to default?
Open Settings and click Reset to defaults in the section you changed, then click again to confirm. Reset all settings at the bottom of the list resets every section.
Why did my settings disappear?
Settings are stored in your browser. A private window, another browser or clearing site data starts from the defaults again.
What is the default bond length in MolDraw?
The default bond length is 45 px with a 30 degree angle snap. Change both in Settings, Style and Bonds.
Do settings sync between my devices?
No. Each browser keeps its own settings. Set them again on each device, or use a style preset to get the same look in one click.
Last updated: