Tree Outliner

A text outliner for nonlinear thinking.

"No army can stop an idea whose time has come." — Victor Hugo

One document, two views: the familiar vertical list and a horizontal tree.

The document is live. Type directly in it. Enter new line · Tab indent · Shift+Tab outdent · Option+↑↓ move · the dot beside a line collapses its branch

Tree Outliner is a tool for structuring your thoughts quickly. It pairs the simplicity of a text outliner with the clarity of organizing ideas spatially.

Capture thoughts quickly, build a hierarchy, adjust nesting, move things around, collapse and expand branches.

capture thoughts
build a hierarchy
adjust nesting
move things around
collapse and expand branches

The horizontal view makes the outliner especially well suited to nonlinear thinking. It lets you see the structure of your thoughts spatially: how ideas connect, how one idea leads to another, and how each branch develops.

You keep working with ordinary text, and the tree is built automatically, without drawing diagrams or positioning elements manually.

What's new

1.0.9 · October 23, 2026

  • Hide Completed (View menu, ⇧⌘H) hides checked items together with their branches. Each document remembers whether the filter is on.
  • Move Completed to Archive (Edit menu) moves every checked item into an Archive branch at the end of the document in one step; ⌘Z brings them back.
  • Work with several items at once: ⇧↑, ⇧↓ or ⇧-click selects neighboring items, ⌘-click picks items anywhere in the document, as in Finder, and ⌘A selects every visible item. Delete, indent, move, duplicate, copy, cut, the checkbox, labels and formatting apply to all of them.
  • Bold and underline are now on ⌘B and ⌘U. The old shortcuts still work.
  • The command palette (⇧⌘P) shows your three most recent commands at the top.
  • Settings → Appearance → Strike through checked items draws checked titles gray and crossed out, in any item style.
  • A new item style, No checkboxes, for outlines of ideas rather than tasks.
  • In the tree, column borders are visible and can be dragged to any width; double-click a border to reset it. The widths are saved with the document. On Lines with margin paper, the red margin follows the first column and starts at the first line.
  • Fixed a crash when showing the sidebar.

1.0.8 · October 16, 2026

  • Notes understand simple Markdown: bold, italic, code and links show formatted in the tree, the list and on paper, and links open with a click. While you type a note in the inspector, the markup is highlighted.
  • Settings are organized into tabs: General, Appearance, Editing, Files and License.
  • New option in Settings → Files: autosave clears the “Edited” mark under the document title.
  • The sidebar keeps the same width in every tab, and the selection stays in the section you clicked.

1.0.7 · October 15, 2026

  • Long notes stay out of the way: in the tree and the list a note longer than two lines shows as its first line with a small icon. Read and write the whole note in the inspector; ⌘' opens it there.
  • In the inspector the note comes last and takes the full height, and the inspector can be made much wider. Return starts a new line in the note.
  • Color labels can fill the whole item instead of showing a dot: Settings → General → Color label → Item background.
  • The view switch moved out of the inspector; use the toolbar or the View menu.
  • The Settings window fits smaller screens: its panes scroll.

1.0.6 · October 15, 2026

  • Printing (⌘P): print the tree or the map as it looks on screen — fitted to one page or at actual size across several sheets — or as a list with every item. Choose in the print panel; Save as PDF works from there too.
  • A new item style that matches the web version: Settings → General → Item style → As in the web version. Dots instead of checkboxes and triangles, a click on a dot folds its branch, checked items get a checkmark and are struck through.
  • The line beside first-level items in the tree can be turned off in Settings → General.
  • A new item always gets the cursor, even if you were typing in the inspector or the search field.
  • Titles and notes typed in the inspector show in the item as you type.
  • Text after an emoji keeps its look when you start editing it.
  • The sample documents now show multi-line titles (⌥↩) and longer notes (⌘').

1.0.5 · October 14, 2026

  • Map, a third view of your document (⌘3): every parent sits centered beside its children, with curved lines and a frame around each item.
  • Bold (⌃⌘9) and underlined (⌃⌘8) item titles, also in the Format menu.
  • Pressing the same color label shortcut again removes the label; another number changes the color.
  • In the tree and on the map, Tab adds a child item; in the list it still indents.
  • ⌘← on an item with nothing to collapse folds its parent and moves the selection there.
  • ⇧⌘O on the root of a hoisted branch returns to the whole document.
  • Highlight Branch can be green: Settings → General → Highlight color. A new Sage paper color goes with it.
  • Japanese.

1.0.4 · October 13, 2026

  • Highlight Branch for the tree view: the selected item, its parents and its whole branch stay bright, the lines between them take the accent color, and everything else fades. Turn it on with the new toolbar button, View → Highlight Branch (⌥⌘P) or in Settings → General.
  • The color labels button left the default toolbar to make room; labels are still in the Format menu, on ⌃⌘1–7 and in Customize Toolbar. The toolbar returns to its default layout once after this update.

1.0.2 · October 12, 2026

  • Paper for your documents. Settings → General → Document background: dots, fine dots, crosses, lines, lines with margin, grid, stripes, and, for the tree, level columns and level borders.
  • Paper color: white, warm, yellow or blueprint.
  • Lines with margin put the red line after the first column of the tree, like the margin of a notebook; a slider sets how wide that column is.
  • On macOS 26.1 and later you can choose how the edge under the toolbar looks: automatic, soft or sharp.

1.0.1 · October 12, 2026

  • Six more languages: French, Spanish, Italian, Portuguese (Brazil), Dutch and Polish.
  • A Command Palette button in the toolbar: click it to see every command and its shortcut.
  • A Settings button at the bottom of the library.
  • Hoist left the default toolbar to make room; it is still on ⇧⌘O, in the menu and in Customize Toolbar. The toolbar returns to its default layout once after this update.

1.0 · October 12, 2026

A native outliner for Mac. Write your thoughts as a tree: every item can hold a note, a checkbox and a color label, and every branch folds away when you don't need it.

  • Two views of the same document: an outline list and a tree canvas.
  • Keyboard first: create, move, indent and fold items without touching the mouse. A command palette finds the rest.
  • Copy, cut, paste and drag items with their branches — inside a document and between documents.
  • Documents open in tabs or in separate windows.
  • Import and export OPML.
  • English, Ukrainian and German.