Luban Ruler - Feng Shui

LUBAN RULER — DRAG TO ANY SIZE, SEE GOOD OR BAD INSTANTLY

The Luban ruler (魯班尺) is the traditional feng shui measuring tool used to pick auspicious dimensions — and avoid inauspicious ones — for doors, furniture, altars and home building. This app puts the whole set of Luban rulers on your phone: drag the ruler or type a size, and every ruler gives its verdict on its own line.

◆ 4 RULERS — SHOW 1 TO 4, IN YOUR ORDER
• Clear Opening 52.2 cm (8 sections) — clear width and height of doors, windows, gates
• Yang Dwelling 42.9 cm (8 sections) — overall size of stoves, steps, beds, cabinets, tables
• Yin Dwelling / Ding Lan 38.8 cm (10 sections) — altars, shrine cabinets, ancestral tablets, tombs
• NEW: Classic Luban 46.08 cm — the Ming–Qing standard, for door and gate openings
• Pick the rulers you use and drag ≡ to reorder them; your choice is remembered

Every section and sub-section comes with its name and meaning in plain English.

◆ KEY FEATURES
• Smooth, endless ruler; tap the number box to type a size (mm or inch)
• Instant Good / Bad verdict with section, sub-section and meaning for every visible ruler
• Nearest lucky size: land on a bad section and the app tells you exactly how many mm to add or remove to reach a good one
• ±1 mm fine-tune buttons and a quick reset to zero
• Light ticks as you drag, a clearer one when the first ruler crosses between good and bad (can be turned off)
• Light and dark themes; good sections always stay red
• 3 languages: English, Tiếng Việt, 中文 — switch from the menu
• Works 100% offline — no ads, no data collection

◆ REWRITTEN USER GUIDE
• Real screenshots with every button numbered and explained
• Illustrations showing clear opening (doors) versus overall size (furniture, altars)
• A card for every ruler: what it is for, how to measure, good ranges, worked examples and the meaning of each section

◆ HOW TO USE
1. Measure the real object with a tape measure (in millimetres)
2. Drag the ruler or type the size — the red line in the middle marks it
3. Read the line of the ruler that fits your object: ✓ Good, or ✗ Bad with a tip to fix it
Rule of thumb: "use red, avoid black".

◆ NOTE
The on-screen ruler is for looking up feng shui sections by size (measure real objects with a tape measure); it does not replace a physical ruler. Feng shui content is provided for cultural reference.

Developed by Manh Nguyen — manh.work
Feedback: [email protected]