Open Channel Flow Calculator
Manning's equation for trapezoidal, rectangular, and triangular channels. Solve for flow rate, normal depth, critical depth, velocity, slope, or Froude number — with a live cross-section diagram.
Enhanced Slope Calculator
Solve for grade, elevation change, length, or angle from any two known values. Toggle between decimal, percent, and rise/run or grade/angle modes.
Stair Calculator
Enter a start and target elevation and it solves for the best riser/step combination to get there — ranked by closest landing, fewest steps, and exact match. Includes an 8" cinder block variant.
Parking Space Calculator
Enter square footage, parking ratio, and pump count per use type to get required parking spaces for a site.
Nashville Metro Parking Calculator
Required parking per Metro Nashville & Davidson County Code of Ordinances §17.20.030, Table 17.20.030. Built-in rounding rules and engineer-study flags.
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