Construction & Engineering
Heavy duty tools for contractors, builders, and DIY projects.
Tire Size Calculator
Compare two tire sizes. Check speedometer error, diameter difference, and sidewall height changes.
Mulch Calculator
Calculate how much mulch you need in cubic yards and bags. Estimate costs for flower beds and landscaping.
Roofing Calculator
Estimate roof area, number of squares, and shingle bundles needed based on house dimensions and pitch.
BTU Calculator
Calculate the required BTU capacity for air conditioners or heaters based on room size and insulation.
Electricity Calculator
Calculate electricity costs for any appliance. Estimate daily, monthly, and yearly energy bills based on power consumption (Watts).
Gravel Calculator
Estimate tons and cubic yards of gravel, sand, or topsoil needed for your project. Supports driveways and circular beds.
Tile Calculator
Calculate how many tiles you need for floors and walls. Estimate boxes required including waste allowance.
Ohms Law Calculator
Calculate voltage, current, resistance, and power. Find any two variables given the others using Ohm's Law.
Resistor Calculator
Identify resistor values by color bands. Supports 4-band and 5-band resistors with tolerance calculation.
Stair Calculator
Calculate rise, run, and stringer length for building stairs. Optimize step height and tread depth.
Horsepower Calculator
Calculate car horsepower from Torque/RPM or 1/4 mile drag racing times.
Engine Horsepower Calculator
Calculate engine horsepower output from torque and RPM. Useful for engine tuning and performance estimation.
Square Footage Calculator
Calculate sq ft for flooring, painting, and construction. Add multiple rooms and estimate costs.
Concrete Calculator
Estimate cubic yards and bags for slabs.
Voltage Drop Calculator
Calculate voltage drop, percentage loss, and wire size requirements.
Concrete Bag Calculator
Count premix bags needed.
Post Hole Calculator
Concrete for fence posts.
Concrete Volume
Calculate cubic yards.
Concrete Slab
For patios & driveways.
Concrete Block
Count blocks for walls.
Concrete Weight
Calculate mass & tons.
Concrete Cost
Estimate project price.
Pipe Weight
Calculate pipe mass.
Mass Calculator
Calculate mass, density, or volume. Includes presets for common materials like steel, gold, and water.
Density Calculator
Calculate density, mass, and volume. Convert between kg/m³, g/cm³, and lb/ft³.
Right Triangle Calculator
Calculate sides and angles of a right triangle.
Surface Area Calculator
Calculate surface area of 3D shapes.
Distance Calculator
Calculate distance between two points (2D & 3D).
Pythagorean Theorem Calculator
Solve for the hypotenuse or missing leg of a right triangle.
Area Calculator
Calculate area of circles, rectangles, triangles, and more.
Slope Calculator
Calculate slope, distance, and equation of a line.