Density can be a user-facing option

What it is

Mail, spreadsheets and editors often ship Comfortable / Compact. The same person needs sparse on day one and dense on day ninety; sparse on a phone and dense on an external display. When one layout cannot be the answer, making density a user-facing option is cheaper than pretending to fit everyone.

The option has to change how many objects fit. Padding 16 to 14 is a toggle, not a density grade.

Why it happens

Frequency and skill move, and so does width; one layout cannot track both axes. Two or three grades hand the fit to the person who has the information. The cost is a test matrix multiplied by the grades: compact will press minimum touch sizes, wrapping, sticky header height; comfortable will scroll a comparison that had been co-visible.

The grade also has to persist across sessions. Resetting to sparse every launch trains experts to ignore the control. If compact only applies to one page, it looks broken. Density is a global (or at least workbench-level) layout parameter, not a per-widget souvenir.

Where it stops holding

One-shot public pages, checkouts, legal consent: no path to skill, no returning visitor to flip a switch. Skip the option. On touch-only devices, compact may undershoot hit-target floors; then there is no compact, or compact only trims vertical air and does not shrink the tap. Assistive large type and OS display zoom already change density. Product options should multiply with those settings, not fight them into a double transform.

Applying it

• Ship two noticeable grades (three if you must): comfortable and compact. Compact should reveal at least ~30% more rows, or bring comparison fields back onto one screen.
• Persist the choice on the account or the device and apply it across workbench surfaces; not one switch per table.
• Floor compact: minimum tap height and row height. Items that cannot meet the floor do not get tighter.
• How to check: walk a critical path (search, compare, submit) on both grades with the same account. Measure every tappable’s height in compact; anything under the platform floor goes back to comfortable size for that item. Then see whether the five-way comparison scrolls again in comfortable — if it does, comfortable still owes a way to keep those five available (frozen headers), not a shrug. Kill the app and reopen; the grade should still be there.

Related

• Same group: F2.07.1 Density has to match how often and how expertly the screen is used · F2.07.2 Sparse layouts levy a paging and scrolling tax
• Nearby: F4.16 Dynamic type and user font size · F2.16 Extreme content and overflow · J5.09 How screen readers work
• Search terms: display density · compact mode · comfortable density · hit target