Files & export

Linked Files

Section-Level Linking

Link external text files to any section. Content auto-refreshes when the file changes.

  • Supported formats: .txt, .rtf (rich text converted to inline tags), .md and .markdown
  • File watching: real-time monitoring with multiple fallback strategies
  • Atomic save detection: handles editors that write-then-rename

Per-Grid-Item Linking

In Columns & Rows sections, each grid cell can link to a different external file with independent file watchers.

Generated Text (Adhesion)

Hellbox can write proof text for you, using only the glyphs your font actually has outlines for. Click the wand button under the content editor and the section’s text is generated from each font’s drawn glyphs: adhesion text, in the tradition of adhesiontext.com. Encoded-but-empty glyphs don’t count; only letters with real geometry make it into the text.

  • Per-font pages: each font’s page generates from its own inventory, so an in-progress Hairline gets sparser text than the finished Bold on the adjacent page, and the text grows as you draw.
  • Stable, seeded generation: saving new glyphs in your editor extends the text instead of rerolling it. The dice button rerolls; every drawn letter is guaranteed to appear at least once.
  • Length: Short, Medium, or Long (roughly 25, 110, or 300 words). With font size set to Auto, the word count tops itself up so the page fills edge to edge.
  • Detach: the pencil button freezes the exact text you’re looking at into ordinary editable content, so you can generate a starting point and hand-tune it.
  • Where it works: Simple text sections, Waterfall (as a single display phrase), and Columns & Rows, either the whole section or individual cells (a cell generates from its own assigned font).
  • Coverage readout: while a font is incomplete, a caption under the editor lists which letters aren’t drawn yet.

Sparse fonts fall back to constructed nonsense words from whatever letters exist, the traditional early-stage spacing text.

Generated text in the content editor: the wand, reroll, and detach controls with the coverage readout

PDF Export

Export & Export As

Hellbox remembers where each document exports. Export PDF (Shift+Cmd+E) silently re-exports to the document’s remembered destination with the last-used options, so iterating is one keystroke. Export PDF As (Option+Shift+Cmd+E) always opens the save panel, prefilled with the remembered name and location. The first-ever export of a document always shows the panel.

The save panel includes three options: Combine with other open documents (one PDF from every open proof), Exclude markup pages, and Open PDF after saving.

Appearance Modes

  • Built-in: Light, Dark, Sepia, High Contrast
  • Custom modes: user-defined background and foreground colors, with a swap button to flip them
  • Per-document mode override
The same proof in three appearance modes: Light, Dark, and a custom orange-on-coral The same proof in three appearance modes: Light, Dark, and a custom orange-on-coral

Page Dimensions

30 named presets across 5 categories, plus Custom:

  • Paper (5): A4, A5, A6, Letter, Tabloid
  • Desktop (6): MacBook Air, MacBook Pro 14”/16”, Desktop, Wireframes, TV
  • Presentation (2): Slide 16:9, Slide 4:3
  • Tablet (5): iPad mini, iPad Pro 11”/12.9”, Surface Pro 8, Android Expanded
  • Phone (12): iPhone SE through iPhone 16 Pro Max, Android Compact and Medium
  • Custom: arbitrary width and height

A swap button flips width and height for landscape (the preset switches to Custom), and typing dimensions by hand auto-detects a matching preset. Margins are independent: top, bottom, left, right.

Headers & Footers

Six tokens can each go in a left, center, or right slot on independent top and bottom bands:

  • Title: the section name
  • Font information: family and style of the fonts on the page
  • Font version: reads the version from the font’s name table, shown like “v1.234”
  • Page number
  • Date & time: with a “Print only” option
  • Custom text: your own string

Hellbox can also print an active OpenType features line that lists every feature turned on for the fonts on the page (for example “Features: salt, ss01, ss02”); it gets its own full-width line so a long list wraps instead of being clipped, and you can place it at the top or bottom, with its own “Print only” option. “Print only” keeps the timestamp and features line out of the on-screen preview while still printing them on export. Either band can be turned off.

Fit to Page

One-click optimization that calculates the optimal font size, line height, and letter spacing to fill a single page. Uses binary search with 0.5pt precision and adapts its strategy for each section type.

Templates

Built-In Templates

Predefined proof setups organized by category:

  • Hamburgers (3): Hamburgefonts, Hamburged Spacing, Hamburged Trio
  • Spacing (3): Basic Character Set, Spacing Test, Trio Spacing
  • Pangram (8): Wizards, Waltz, Dwarf, Sphinx, Zebras, Boxing, Jackdaws, Liquor
  • Kerning (4): I Ask Jeff, Kerning Trio, Extra Kerning Words, Furniture Characters
  • Diacritics (26 languages): Afrikaans through Turkish
The Welcome window: start a document from a built-in proof template, with recents and starred templates The Welcome window: start a document from a built-in proof template, with recents and starred templates

Custom Templates

Two levels of reusable templates:

  • Document templates (.fpt): save the whole document, sections, fonts, and page setup included, with Save Document as Template (Option+Shift+Cmd+T)
  • Section templates (.fps): save a single section with Save Section as Template (Shift+Cmd+T)

Both can be starred for quick access in the template picker, and the templates folder is one click away via File > Reveal Templates Folder in Finder.

The Section Templates picker: 44 templates by category, multi-select, added to the open document The Section Templates picker: 44 templates by category, multi-select, added to the open document