Engineering and science calculators with step-by-step solutions
142 free calculators for engineering, physics, chemistry, statistics, finance and nursing. Every result comes with the full worked solution.
Electrical
21- Series and parallel resistor calculatorSeries & parallel resistors
- Voltage divider calculatorSeries & parallel resistors
- RC time constant calculatorRC & RL transients
- RLC impedance calculatorAC impedance & phasors
- Power factor correction calculatorAC power & power factor
- Op-amp gain calculatorOp-amp circuits
- Three-phase power calculatorThree-phase power
- Transformer turns ratio calculatorTransformers
- Resonant frequency calculator (LC and RLC)LC resonance, Q factor & bandwidth
- LED resistor calculatorDiodes & transistors
- Inverse Laplace transform calculator (partial fractions)Laplace transforms
- Voltage drop calculatorThree-phase power
- 555 timer calculator (astable and monostable)Diodes & transistors
- Decibel calculator (dB, dBm and sound levels)Bode plots & margins
- Bode plot calculator (gain and phase margin)Bode plots & margins
- Routh–Hurwitz stability criterion calculatorStability: Routh–Hurwitz & root locus
- Laplace transform calculatorLaplace transforms
- Thévenin and Norton equivalent calculatorThévenin & Norton
- Ohm’s law calculator (voltage, current, resistance and power)Series & parallel resistors
- Resistor colour code calculator (4, 5 and 6 bands)Series & parallel resistors
- Capacitor calculator (series, parallel, charge and energy)RC & RL transients
Mechanical
18- Beam reaction calculatorBeam support reactions
- Shaft torsion calculatorTorsion of shafts
- Axial stress and strain calculatorAxial stress & strain
- Mohr’s circle calculatorMohr’s circle & stress transformation
- Gear ratio calculatorGears & gear trains
- Projectile motion calculatorProjectile motion
- Bernoulli equation calculatorContinuity & Bernoulli
- Heat conduction calculatorHeat conduction
- Carnot efficiency and COP calculatorHeat engines & refrigerators
- Pipe head loss calculator (Darcy–Weisbach)Pipe friction & head loss
- Pump power calculatorPumps & pump power
- Natural frequency and damping calculatorMechanical vibrations
- Otto and Brayton cycle efficiency calculatorGas power cycles
- Reynolds number calculatorPipe friction & head loss
- Thermal expansion calculatorAxial stress & strain
- Belt length calculator (open and crossed belts)Gears & gear trains
- Kinetic energy calculator (and potential energy, work and power)Work & energy
- Torque calculator (force, power and rpm)Rigid-body rotation
Civil
10- Beam deflection calculatorBeam deflection
- Shear force and bending moment diagram calculatorShear force & bending moment
- Euler buckling calculatorColumn buckling
- Manning equation calculatorOpen-channel flow (Manning)
- Consolidation settlement calculatorConsolidation settlement
- Moment of inertia calculator (second moment of area)Centroid & second moment of area
- Bending stress calculator (σ = My/I)Shear force & bending moment
- Centroid calculator (composite shapes and polygons)Centroid & second moment of area
- Truss calculator (method of joints)Truss: method of joints
- Density calculator (mass, volume and density)Hydrostatic force
Chemical
4Computer science
3Mathematics & statistics
24- Z-score and normal probability calculatorNormal distribution
- Confidence interval calculatorConfidence intervals
- Sample size calculatorConfidence intervals
- Mean, median and standard deviation calculatorDescriptive statistics
- Linear regression calculatorLinear regression & correlation
- Chi-square goodness-of-fit calculatorChi-square tests
- Matrix determinant and inverse calculatorMatrices & determinants
- Normal distribution calculatorNormal distribution
- Binomial distribution calculatorProbability
- Poisson distribution calculatorProbability
- Permutation and combination calculator (nPr and nCr)Probability
- t-test calculatorHypothesis tests & confidence intervals
- P-value calculatorHypothesis tests & confidence intervals
- Correlation coefficient calculator (Pearson and Spearman)Linear regression & correlation
- Eigenvalue and eigenvector calculatorMatrices & determinants
- One-way ANOVA calculatorHypothesis tests & confidence intervals
- Expected value and variance calculatorProbability
- Half-life and exponential decay calculatorDifferential equations
- Significant figures calculator (count, round and calculate)Descriptive statistics
- Percent error calculator (and percent difference)Descriptive statistics
- Quadratic equation solver (ax² + bx + c = 0)Complex numbers
- System of linear equations solver (2×2 and 3×3)Matrices & determinants
- Derivative calculator with stepsDerivatives
- Integral calculator (definite and indefinite)Integrals
Natural sciences
10- Molarity calculatorMolarity & dilution
- Dilution calculator (C1V1 = C2V2)Molarity & dilution
- pH calculatorpH & buffers
- Specific heat calculator (q = mcΔT)Calorimetry & enthalpy
- Henderson–Hasselbalch buffer calculatorpH & buffers
- Percent yield calculatorStoichiometry
- Punnett square calculatorGenetics
- Stoichiometry calculator (grams to grams and limiting reactant)Stoichiometry
- Molar mass calculatorStoichiometry
- Empirical formula calculator (and molecular formula)Stoichiometry
Physics
10- Kinematics calculator (SUVAT)Kinematics
- Centripetal force calculatorCircular motion
- Collision and momentum calculatorMomentum & collisions
- Coulomb’s law calculatorCoulomb’s law & electric fields
- Pendulum and spring period calculatorSprings & pendulums
- Spring constant calculator (Hooke’s law)Springs & pendulums
- Free fall calculator (time, height and impact speed)Kinematics
- Engineering unit converterNewton’s laws
- Magnetic field calculator (wire, loop, solenoid and toroid)Magnetic fields & induction
- Acceleration calculator (and average velocity)Kinematics
Medicine
1Nursing
31- Dosage calculator (desired over have)Dosage calculations
- IV flow rate and drip rate calculatorIV infusion rates
- Weight-based dose calculator (mg/kg)Dosage calculations
- Body surface area calculator (BSA)Pharmacy calculations
- mcg/kg/min to mL/h calculator (weight-based infusion)Pediatric & critical-care dosing
- Reconstitution calculator (powder volume and concentration)Pharmacy calculations
- Pediatric safe dose range calculator (mg/kg/day)Pediatric & critical-care dosing
- Loading dose and maintenance dose calculator (pharmacokinetics)Clinical pharmacokinetics
- IV infusion time calculator (when will the infusion finish?)IV infusion rates
- Nursing unit converter (mg, mcg, kg, lb, mL, tsp, °F, °C)Nursing math & unit conversions
- Glasgow Coma Scale calculator (GCS and GCS-P)Clinical assessment scores
- APGAR score calculatorClinical assessment scores
- Braden scale calculator (pressure injury risk)Clinical assessment scores
- Morse fall scale calculator (fall risk)Clinical assessment scores
- NEWS2 score calculator (National Early Warning Score 2)Clinical assessment scores
- Mean arterial pressure calculator (MAP)Nursing fundamentals
- QTc calculator (Bazett, Fridericia and Framingham)ECG rhythm strip interpretation
- ECG heart rate calculator (300, 1500 and 6-second methods)ECG rhythm strip interpretation
- BMI calculator (body mass index for adults)Enteral & parenteral nutrition calculations
- Ideal body weight calculator (Devine) and adjusted body weightEnteral & parenteral nutrition calculations
- Tube feeding calculator (enteral rate, calories, protein, free water)Enteral & parenteral nutrition calculations
- Oxygen cylinder duration calculator (tank factor)Oxygen therapy & respiratory calculations
- P/F ratio calculator with FiO2 estimate (nasal cannula)Oxygen therapy & respiratory calculations
- Sensitivity, specificity, PPV and NPV calculator (2×2 table)Evidence-based practice statistics
- NNT calculator (number needed to treat, ARR, RRR)Evidence-based practice statistics
- Intake and output calculator (fluid balance)IV fluids & fluid balance
- Parkland formula calculator (burn fluid resuscitation)IV fluids & fluid balance
- Anion gap calculator (albumin-corrected, delta ratio)Arterial blood gas interpretation
- Alligation calculatorPharmacy calculations
- Heparin infusion rate calculatorPediatric & critical-care dosing
- Maintenance fluids calculator (Holliday–Segar)IV fluids & fluid balance
Business & economics
10- Compound interest calculatorTime value of money
- Loan payment calculatorTime value of money
- NPV and IRR calculatorNPV & IRR
- Bond price calculatorBond pricing & yield
- WACC calculatorCAPM & WACC
- CAPM calculatorCAPM & WACC
- Depreciation calculatorDepreciation
- Break-even point calculatorBreak-even analysis
- ROI calculator (return on investment)NPV & IRR
- Payback period calculator (simple and discounted)NPV & IRR