How to use the Minecraft arch generator
Width controls the outside span, height controls the rise from the baseline to the crown, and thickness controls the number of blocks around the opening. Build one half from the chart and mirror it across the center line.
Doorway and window arches
Odd widths provide one center block at the top. Even widths create a two-block center, which often aligns better with double doors and broad windows. Add straight pillars below the generated curve when the opening needs more vertical clearance.
Bridge and tunnel arches
For structural builds, treat the chart as the visible façade rather than a physics calculation. Extend the same arch backward to create a tunnel or repeat it along the bridge, then connect the ribs with matching blocks.
Round versus tall arches
Equal width and height produce a rounded opening. Increasing height makes a taller ellipse-like arch; increasing width produces a flatter span. Use the oval generator when you need the complete closed ellipse.