Explore 18 free online geometry and measurement calculators with interactive SVG visualizations, printable calibrated scales, 3D volume analyzers, and precision dimensioning tools.
Regular polygon properties, side lengths, apothems, circumradii, golden diagonals, and internal angles.
Calculate regular octagon area, perimeter, apothem (inradius), circumradius, and span across flats with dynamic geometric SVG rendering and verified formulas.
Calculate regular pentagon area, perimeter, diagonal length, apothem, and circumradius instantly from side length with exact mathematical formulas.
Calculate rhombus area from diagonals (p, q), side length, perimeter, inradius, and interior angles with responsive SVG geometry visualization.
Calculate parallelogram area, perimeter, interior angles, and diagonal lengths from base, side, and height with dynamic geometric SVG visualization.
3D solids, hollow pipes, truncated cones, spherocylinders, triangular prisms, and 2D surface areas.
Calculate the volume of cubes, rectangular prisms, cylinders, spheres, and cones with interactive SVG diagrams and real-time unit conversions to liters and gallons.
Calculate total and lateral surface area for cubes, rectangular prisms, cylinders, spheres, and cones with interactive unfolded 2D net diagrams.
Calculate volume in cubic inches (in³) from dimensions with instant real-time conversions to US liquid gallons, cubic feet, liters, and cubic yards.
Calculate surface area in square meters (m²) from length and width with instant conversions to square feet, acres, hectares, and square centimeters.
Calculate truncated cone volume, slant height, lateral area, base areas, and total surface area from bottom radius, top radius, and vertical height.
Calculate 3D capsule (spherocylinder) volume and surface area, plus 2D stadium area and perimeter from cylinder radius and side length.
Calculate triangular prism volume, base area using Heron's formula, lateral area, and total surface area from 3 triangle sides and prism length.
Calculate hollow tube and pipe volume, wall thickness, inner capacity, and cross-sectional areas from outer radius, inner radius, and pipe length.
Calculate the area, width, average radius, and circumferences of an annulus (circular ring) from outer and inner radii. Fast, precise, and visual.
Calibrated inch fractional scales (1/16", 1/32"), metric millimeter rulers, and multi-strip printable tape measures.
Read and convert fractional inches (1/16", 1/32") with an interactive calibrated ruler scale, instant decimal conversions, and metric millimeter equivalents.
Interactive calibrated metric centimeter ruler. Convert cm to millimeters, meters, decimal inches, and fractional 1/16" marks with visual tick highlights.
Generate and print a true 100% scale paper measuring tape in imperial (1/16" increments) and metric (mm/cm) scales with easy glue overlap tabs.
180° calibrated printable protractor, rotating ray indicators, and geographic DMS to decimal degrees.
Generate and print a 100% physically calibrated 180-degree protractor with interactive rotating angle ray, supplementary angles, and millimeter calibration bar.
Convert geographic coordinates between Degrees Minutes Seconds (DMS) and Decimal Degrees (DD) with quadrant direction (N/S/E/W) and radian output.
Modern geometry calculations combine Euclidean proofs, dimensional unit analysis, and vector trigonometry. Real-time SVG diagrams provide dynamic visual feedback while client-side precision algorithms prevent compounding floating-point inaccuracies.
Rigorous geometric formulas govern regular polygons, Heron's triangular base calculations, and truncated conical frustums with mathematically verified constants.
Linear dimensions, 2D surface areas (m², sq ft), and 3D volumes (m³, in³, gallons) are converted strictly through dimensional exponents rather than linear factors.
Printable tools include built-in millimeter calibration benchmarks to verify physical print dimensions against physical hardware rulers before cutting or folding.
In your browser print dialog, set the scale to "100%" or "Actual Size" rather than "Fit to Page". Measure the included 50 mm calibration bar with a physical ruler to confirm 1:1 true scale.
Lateral surface area measures the area of the sides excluding the top and bottom faces (e.g. 2πrh for a cylinder). Total surface area adds both base areas (e.g. 2πrh + 2πr²).
A hollow tube calculator subtracts inner core volume (πr²L) from outer cylinder volume (πR²L), computing true material volume (π(R² - r²)L) and wall thickness (R - r).
Yes. Negative coordinates or Southern (S) and Western (W) hemispheres automatically apply negative decimal signs for full GIS, GPS, and surveying compatibility.
