Board Size Calculator
Enter your room depth and wall width to get the exact whiteboard or greenboard size your last bench can read. Free tool from Rangoli Creatives, Hyderabad.
Rule of thumb: board height ≈ room depth ÷ 7.5. A 30 ft classroom reads a 4 ft-tall board comfortably from the last bench.
We recommend
4 × 8 ft
A 4 ft-tall board keeps writing readable at 30 ft depth, and 8 ft fits your 12 ft wall with breathing room.