Genba Dentaku
CalculatorsTools
Ctrl+K

Menu

  • Home
  • Calculators
  • Tools

Categories

  • Electrical
  • Structural
  • Civil & Construction
  • HVAC & Piping
  • Networking
  • Estimating

System

Home
Calculators
Civil & Construction
Civil & Construction

Civil & Construction

Civil and earthwork calculators.

CV
New

Culvert Size Calculator

Size a round culvert with Manning's equation. Get the full-flow capacity in cfs and velocity for a diameter, or the minimum standard pipe size for a design flow — concrete, CMP, or HDPE. Free, no sign-up.

Civil & Construction
CV
New

Rational Method Calculator

Estimate peak stormwater runoff with the Rational Method, Q = C·i·A. Build a weighted runoff coefficient from multiple surfaces, enter the rainfall intensity and area, and get the peak flow in cfs. Free, no sign-up.

Civil & Construction
CV
New

Cut and Fill Calculator

Calculate cut and fill earthwork volume with the average end area method. Enter cross-section areas along the alignment to get total cut, fill, and the net import or export in cubic yards. Free, no sign-up.

Civil & Construction
Back to all tools
Genba Dentaku

No install, no signup — just open and calculate.

Service

  • Calculators
  • Toolbox
  • New tools
  • Popular tools
  • Guide
  • SortPDF — auto-sort PDF drawings

Support

  • News
  • FAQ
  • Contact

About & Legal

  • About
  • Terms of Use
  • Privacy Policy
  • Disclaimer

About the creator

  • Pybes — Run Python without Python
  • reiridge portfolio

© 2026 Genba Dentaku. All rights reserved.

日本語