Online Engineering Tools
Practical, free calculators for civil engineering tasks. Solve structural, hydraulic, and material problems instantly in your browser. No signup required.
All Engineering Tools
Each tool is built on established engineering formulas with unit conversion and visualization.
Post-Construction Cleaning Calculator
Estimate cleaning requirements, time, and manpower needed after construction projects are completed.
Compound Interest Calculator and Visualizer
Calculate compound interest over time and visualize the growth of investments with interactive charts.
Carbon Footprint Calculator
Estimate your personal or household carbon emissions based on lifestyle choices and energy use.
Bending Stress Calculator
Calculate the bending stress in beams using moment, section modulus, and cross-sectional dimensions.
Simultaneous Equation Solver
Solve systems of two or three linear equations instantly with step-by-step solutions.
Mass, Volume, Density Calculator
Compute any one value (mass, volume, or density) when the other two are known, using the density formula.
Learn the Theory
Understand the engineering principles behind each calculator.
Hydrograph: Complete Theory, Unit Hydrograph & Derivation
A hydrograph is a graphical representation of the variation of discharge (or stage) of a stream at a given gauging station plotted against time. In hydrology, it is the single most important tool for understanding and quantifying the rainfall-runoff response of a catchment. Every flood estimate, reservoir design, culvert sizing, and floodplain mapping exercise depends either directly on a measured hydrograph or on a model capable of reproducing one.
3-Point Bending Test Equations
The 3-point bending test (also written as three-point bend test or flexure test) is a standardised mechanical test that measures the flexural properties of a material by loading a beam specimen at its midpoint while it rests on two supports
Hollomon Equation: Strain Hardening Power Law - Formula, Parameters, Worked Examples & K–n Table
he complete reference for the Hollomon power law : derivation, physical meaning of K and n, true-vs-engineering stress-strain conversion, worked examples for annealed copper and structural steel, comprehensive K and n table for 20+
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