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Online services to help you at work and study!
Calculators, generators and trainers: free, no sign-up.
- 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 Onlinenew
- MAC Address Generator Onlinenew
- Shamir Secret Sharing Online (M of N)new
- Resonant orbit calculator
- Least squares method online (linear regression)new
- Curve fitting online (approximation by formula)new
- Numerical integration online (trapezoidal, Simpson, rectangles)new
- Differential equation solver: first order, second-order linear, initial value problemsnew
- Limit calculator with steps: special limits, L'Hôpital's rule, indeterminate formsnew
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- Matrix multiplication online with solution
- Multiply a matrix by a number online
- Matrix transposition online
- Matrix determinant online
- Resistor colour code calculator: 3, 4, 5, 6 bands, E6–E96 series and SMD codesnew
- Heat Calculator and Heat Balance Onlinenew
- Measurement Uncertainty Calculator: Direct and Indirectnew
- Thin Lens and Mirror Calculator with Ray Diagramnew
- Equivalent Resistance and Ohm’s Law Calculator Onlinenew
- Kirchhoff’s Laws Circuit Solver Onlinenew
- AC Circuit Calculator (Phasor Method)new
- Three-phase circuit: star and deltanew
- Nuclear Reaction Calculator: Missing Particle, Q Value, Binding Energynew
- Traverse calculator online (closed and open traverse)new
- Levelling field book and level run adjustment onlinenew
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- Inverse and direct surveying problems onlinenew
- Area from coordinates online (shoelace formula)new
- Survey intersection calculator: forward, resection (Snellius–Pothenot) and distance intersectionnew
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- Limits and fits calculator (ISO 286)new
- Surface roughness calculator: Ra ↔ Rz conversion, roughness classes and drawing symbolnew
- Drive Kinematics and Electric Motor Selectionnew
- Spur and Helical Gear Design Calculatornew
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- Worm gear calculator: centre distance, module, efficiency, thermal checknew
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- Roller chain drive calculator: pitch, sprocket teeth, chain lengthnew
- Shaft calculator: support reactions, moment diagrams, diameter and safety factornew
- Rolling bearing calculator: ball bearing selection by life (GOST 8338-75)new
- Parallel key calculator: key size by shaft diameter (GOST 23360-78) and crushing checknew
- Point kinematics online: velocity, acceleration and trajectory from x(t), y(t)new
- Plane mechanism online: instantaneous centre of velocity, point velocities and accelerationsnew
- Centroid of a plane shape and composite section online: coordinates, first moments, moments of inertianew
- Frame Support Reactions Calculator: Fixed, Pinned, Roller, Compound Structure (Statics)new