Nail Extension Length Calculator

Extension Length is computed as Desired Total Length minus Nail Bed Length with a zero floor (line 17), so every millimeter you add to the target total adds one millimeter of extension beyond the natural free edge — unless the total is shorter than the bed, in which case extension length stays at zero. Nail Bed Width and shape do not enter this subtraction; they influence tip size and area instead.

Shape picks a multiplier on extension width when computing extension area (lines 24-33), which flows into total area and Product Per Nail (lines 37-40). Application Method does not change per-nail volume; it only multiplies the ten-nail total by a waste factor — 1.1 for tips with overlay, 1.25 for sculpted forms, 1.05 for dual forms, 1.15 for poly gel (lines 54-55) — yielding Product for Full Set (mL).

Breakage Risk adds a length component capped at fifty points from extension length divided by fifty (lines 45-46) to a shape component based on how far the shape multiplier sits below a full-width square (line 46), then clamps at one hundred (line 47). Fill Interval starts at three weeks and subtracts extension length divided by thirty, with a minimum of one and a half weeks (lines 50-51), so longer extensions recommend shorter gaps between maintenance appointments.

The engine rounds ten minus nail-bed width minus ten millimeters — effectively ten minus width plus ten — and clamps the result between 0 and 10 (line 21). Wider beds therefore map to smaller tip numbers in this simplified sizing chart. The estimate is a planning shortcut; it does not account for sidewall curvature or brand-specific tip charts.