JUJUMI Engineering Calculators
Free, accurate, instant online engineering calculation platform covering Mechanical, Electrical, Civil engineering and unit conversion — 77+ tools, formulas per ISO / AGMA / ASME.
Mechanical Engineering 38
Mechanical Design
Gear Ratio
Compute the gear ratio between driver and driven gears, outp
Open →Gear Module & Pitch
Compute pitch diameter D, addendum da, root df, circular pit
Open →Bevel Gear Dimensions
Compute pitch cone angle γ, equivalent teeth Zv, cone distan
Open →Gear Undercut & Profile Shift
Determine the minimum teeth Zmin to avoid undercut and the m
Open →Standard Spur Gear Size
Compute pitch, addendum, base diameters, centre distance, ci
Open →Bearing Life (L10)
Compute rated bearing life L10 (10⁶ rev) and L10h (hours). O
Open →Bolt Diameter
Find the minimum required thread major diameter for an axial
Open →Thread Engagement Length
Verify thread-flank shear and bearing stress at engagement l
Open →Riveted Joint
Compute rivet shear capacity, plate bearing pressure, plate
Open →Bending Shaft Diameter
Determine minimum shaft diameter under bending moment for so
Open →Torsion Shaft Diameter
Determine minimum shaft diameter under torsion for solid or
Open →Combined Torsion & Bending
With simultaneous bending M and torque T, find diameter by e
Open →Power Transmission Shaft
Design a power shaft by torsional rigidity (twist ≤0.25°/m)
Open →Shaft/Hole Tolerance
Compute upper/lower deviations and limit sizes at a nominal
Open →Coiled Spring
Compute spring index c, Wahl factor k, torsional stress τ, d
Open →Leaf Spring
Compute bending stress and free-end deflection of a cantilev
Open →Torsion Spring
Compute the bending stress σ, angular deflection θ and torsi
Open →Power & Motion
Strength of Materials
Normal & Shear Stress
Compute normal stress σ (perpendicular force) and shear stre
Open →Strain & Poisson's Ratio
Compute axial strain from original length and deformation, t
Open →Elastic Modulus & Energy
Apply Hooke's law to compute elastic modulus E, shear modulu
Open →Shaft Torsion Analysis
Analyse torsional shear stress and twist angle of solid/holl
Open →Beam Support Reaction
Compute end support reactions of a simply supported beam und
Open →Cantilever — Point Load
Compute max bending moment and free-end deflection of a cant
Open →Cantilever — UDL
Compute max moment and free-end deflection of a cantilever u
Open →Simply Supported — Point
Compute max bending moment (at the load) and deflection at t
Open →Simply Supported — UDL
Compute max mid-span moment and mid-span deflection of a sim
Open →Moment of Inertia & Section Modulus
Compute moment of inertia I and section modulus W for rectan
Open →Bending Stress
Compute bending normal stress σ = M/W from bending moment an
Open →Beam Shear & Moment
For a simply supported beam with a point load, compute react
Open →Thermal & Fluid
Machining
Cutting Speed & RPM
Compute cutting speed from diameter and RPM, or spindle RPM
Open →Three-Wire Thread
Compute thread pitch diameter d₂ from a three-wire measureme
Open →Base Tangent Length
Compute span number k and base tangent length W for standard
Open →Sheet Metal Drawing
Compute drawing ratio m and first-draw punch force F = π d t
Open →Sheet Metal Blanking
Compute blanking force F = π d t τ and punch face compressiv
Open →Electrical Engineering 7
Electrical Engineering
Ohm's Law
Given any two of voltage U, current I, resistance R, solve t
Open →Current Intensity
Compute average current from I = Q/t, with reverse solutions
Open →Resistance Formula
Compute conductor resistance R and conductance G=1/R from re
Open →Motor Rated Torque
Based on T = 9550 P/n: torque from power & speed, power from
Open →Joule's Law
Compute heat Q = I² R t from current, resistance and time; r
Open →Equivalent Resistance
Compute equivalent resistance of resistors in series or para
Open →Electric Work
Compute electrical energy from W = U I t and convert to joul
Open →Civil Engineering 3
Unit Conversion 29
Basic Physical Quantities
Length Converter
Instantly convert Length between SI and common engineering u
Open →Mass Converter
Instantly convert Mass between SI and common engineering uni
Open →Area Converter
Instantly convert Area between SI and common engineering uni
Open →Volume Converter
Instantly convert Volume between SI and common engineering u
Open →Mechanics & Strength
Force Converter
Instantly convert Force between SI and common engineering un
Open →Pressure Converter
Instantly convert Pressure between SI and common engineering
Open →Stress Converter
Instantly convert Stress between SI and common engineering u
Open →Torque Converter
Instantly convert Torque between SI and common engineering u
Open →Moment of Inertia Converter
Instantly convert Moment of Inertia between SI and common en
Open →Section Modulus Converter
Instantly convert Section Modulus between SI and common engi
Open →Dynamics & Motion
Power Converter
Instantly convert Power between SI and common engineering un
Open →Speed Converter
Instantly convert Speed between SI and common engineering un
Open →Acceleration Converter
Instantly convert Acceleration between SI and common enginee
Open →Volumetric Flow Rate Converter
Instantly convert Volumetric Flow Rate between SI and common
Open →Angular Velocity Converter
Instantly convert Angular Velocity between SI and common eng
Open →Energy & Refrigeration
Energy Converter
Instantly convert Energy between SI and common engineering u
Open →Work Converter
Instantly convert Work between SI and common engineering uni
Open →Heat Converter
Instantly convert Heat between SI and common engineering uni
Open →Refrigeration Converter
Instantly convert Refrigeration between SI and common engine
Open →Temperature Converter
Instantly convert Temperature between SI and common engineer
Open →Fluid & Chemical
Mass Flow Rate Converter
Instantly convert Mass Flow Rate between SI and common engin
Open →Density Converter
Instantly convert Density between SI and common engineering
Open →Dynamic Viscosity Converter
Instantly convert Dynamic Viscosity between SI and common en
Open →Kinematic Viscosity Converter
Instantly convert Kinematic Viscosity between SI and common
Open →Concentration Converter
Instantly convert Concentration between SI and common engine
Open →Specific Volume Converter
Instantly convert Specific Volume between SI and common engi
Open →