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Credit calculator with early repayment online
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English verb conjugation
Password generator online
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Unit converter online (pressure, force, power, energy)
For programmers
For programmers
Online colour contrast checker
RGB ↔ HSV converter online
Online unix timestamp calculator
Regular expression tester (regex online)
HTTP headers checker
md5 online, md4, sha1
Online base64_encode, base64_decode
Convert images to base64 code (Image to base64)
Online urlencode, urldecode
Online php serialize unserialize
SSH Key Generator Online
MAC Address Generator Online
Shamir Secret Sharing Online (M of N)
Mathematics
Mathematics
Resonant orbit calculator
Interpolation and Extrapolation online (linear interpolation/extrapolation)
Interpolation - Newton polynomial (online calculator)
Interpolation - Lagrange polynomial (online calculator)
Bilinear interpolation (double linear interpolation)
Table interpolation online (linear, spline, inverse)
Least squares method online (linear regression)
Curve fitting online (approximation by formula)
Numerical integration online (trapezoidal, Simpson, rectangles)
Differential equation solver: first order, second-order linear, initial value problems
Limit calculator with steps: special limits, L'Hôpital's rule, indeterminate forms
Function analysis and graph: domain, asymptotes, extrema, inflection points
Quadratic equation solver (quadratic equation online)
Root finding online (bisection, Newton, regula falsi, secant)
System of linear equations solver (Gauss, Cramer, Seidel)
Matrix multiplication online with solution
Multiply a matrix by a number online
Matrix transposition online
Matrix determinant online
Geometry
Geometry
Distance between two points in space (calculate online)
Triangle Solver Online: Sides, Angles, Area, Altitudes, Medians
Cube volume
Parallelepiped volume
Pyramid volume
Sphere volume
Cylinder volume
Cone volume
Prism volume
Regular tetrahedron volume
Truncated cone volume
Truncated pyramid volume
Physics
Physics
Heat Calculator and Heat Balance Online
Measurement Uncertainty Calculator: Direct and Indirect
Thin Lens and Mirror Calculator with Ray Diagram
Equivalent Resistance and Ohm’s Law Calculator Online
Kirchhoff’s Laws Circuit Solver Online
AC Circuit Calculator (Phasor Method)
Three-phase circuit: star and delta
Nuclear Reaction Calculator: Missing Particle, Q Value, Binding Energy
Hydraulics and heat engineering
Hydraulics and heat engineering
Pipe Head Loss Calculator Online: Reynolds Number, Friction Factor
Psychrometric chart online: moist air properties and processes
Steam tables and h-s (Mollier) chart online (IAPWS-IF97)
Engineering surveying
Engineering surveying
Traverse calculator online (closed and open traverse)
Levelling field book and level run adjustment online
Tacheometric survey calculator: field book reduction, contour plan and 3D terrain
Setting out design elevations with a level: staff reading, grade line, cut and fill
Inverse and direct surveying problems online
Area from coordinates online (shoelace formula)
Survey intersection calculator: forward, resection (Snellius–Pothenot) and distance intersection
Map scale calculator: representative fraction, verbal scale, scale accuracy, distances and areas
Machine design and metrology
Machine design and metrology
Limits and fits calculator (ISO 286)
Surface roughness calculator: Ra ↔ Rz conversion, roughness classes and drawing symbol
Drive Kinematics and Electric Motor Selection
Spur and Helical Gear Design Calculator
Gearbox Course Project Wizard: Drive and Gear Design Step by Step
Worm gear calculator: centre distance, module, efficiency, thermal check
V-belt drive calculator: section, pulleys, belt length, number of belts
Roller chain drive calculator: pitch, sprocket teeth, chain length
Shaft calculator: support reactions, moment diagrams, diameter and safety factor
Rolling bearing calculator: ball bearing selection by life (GOST 8338-75)
Parallel key calculator: key size by shaft diameter (GOST 23360-78) and crushing check
Theoretical mechanics
Theoretical mechanics
Point kinematics online: velocity, acceleration and trajectory from x(t), y(t)
Plane mechanism online: instantaneous centre of velocity, point velocities and accelerations
Centroid of a plane shape and composite section online: coordinates, first moments, moments of inertia
Frame Support Reactions Calculator: Fixed, Pinned, Roller, Compound Structure (Statics)
Strength of materials
Strength of materials
Beam calculator: support reactions and shear and moment diagrams
Beam section selection online: I-beam, channel, round, timber by strength and deflection
Biology
Biology
Child blood type calculator: ABO and Rh inheritance
Punnett Square Calculator: Monohybrid, Dihybrid and Trihybrid Cross
Chemistry
Chemistry
Complete a chemical reaction: predict the products and balance
Balance a chemical equation online
Probability
Probability
Law of total probability and Bayes' theorem calculator with a probability tree
Discrete random variable: distribution table, mean, variance and CDF online
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Chemistry
Chemistry
Complete a chemical reaction: predict the products and balance
Balance a chemical equation online