🧮Calculators
Calculators cover finance, health, math, physics, engineering and everyday life: interest and loans, net salary, BMI, rule of three, conversions and more. Results are informational and educational — for important decisions, confirm with a professional and official sources.
2826 tools
Study Time per Subject Goal
Calculates weekly study hours needed to reach study goal per subject by a deadline.
Book Reading Time by Pages
Estimates hours and days to read a book from total pages and daily pace.
Reading Speed in Words per Minute
Calculates reading speed in words per minute from time spent and total words.
Ideal Resume Pages by Experience
Suggests ideal resume page count based on years of professional experience.
Exam Questions Needed to Pass
Calculates how many questions you need to get right on an exam to reach passing grade.
College Entrance Score Target for a Course
Shows target college entrance points needed to enroll in competitive Brazilian courses.
Enem Score Needed for Medicine
Shows average Enem SISU cutoff scores for Medicine course at Brazilian universities.
Enem Score Needed for Law
Shows average Enem SISU cutoff scores for Law course at Brazilian universities.
Wedding Gifts by Number of Guests
Estimates average number of wedding gifts received based on guest count.
Event Drinks per Guest
Estimates liters of soda, juice, water and alcohol per person at a multi-hour party.
Event Food per Guest
Estimates grams of food (snacks, main course, dessert) per person at an event.
Average Dating Time Before Marriage in Brazil
Shows average dating time before marriage in Brazil and compares with your current relationship.
Valentines Day Gift Budget
Suggests Valentines Day gift budget based on relationship length.
Kids Birthday Gift Budget
Suggests kids birthday gift budget based on child age and relationship.
Kids Birthday Party Budget
Estimates total kids birthday party budget based on guest count.
Baby Shower Budget by Guests
Estimates total baby shower budget from guest count and average cost per person.
College Graduation Budget
Estimates total college graduation budget including ball, dinner and photo.
Sweet 15 Party Budget
Estimates total sweet 15 party budget based on guest count.
Playlist Songs Needed by Duration
Calculates how many songs are needed for a party playlist based on total duration.
Wedding Album Photo Count
Estimates number of photos to deliver in a wedding album based on pages and style.
Admissible Stress for Steel and Concrete
Computes admissible stress for steel and concrete given characteristic strength and safety factor.
Simply Supported Beam Deflection
Computes max deflection of a simply supported beam under uniformly distributed load.
Maximum Bending Moment Beam
Computes maximum bending moment for a simply supported beam (UDL or central point load).
Beam Shear Stress
Computes max shear stress for a rectangular beam under a shear force.
Beam Bending Stress
Computes bending normal stress on a beam from bending moment and section modulus.
Column Compression Stress
Computes compression stress on a column from axial load and section area.
Euler Column Buckling
Computes critical buckling load (Pcr) of a slender column using Euler formula.
Rebar Area Concrete Beam
Simplified estimate of longitudinal rebar area for a reinforced concrete rectangular beam.
Concrete Volume Beam
Computes concrete volume in cubic meters needed for a rectangular beam.
Structural Safety Factor
Computes the safety factor (FS) as the ratio of resisting load to applied load.
Two-way Slab Deflection
Computes max deflection of a simply supported rectangular slab under uniform load.
Steel Poisson Coefficient
Computes lateral strain from Poisson ratio and axial strain for a steel bar.
Pavement Traffic Resistance
Estimates N (equivalent standard axle operations) for pavement design under Brazilian DNIT method.
Molarity by Mass and Volume
Computes molar concentration (mol/L) from solute mass, molar mass and volume.
Molality by Solvent Mass
Computes molality (mol/kg) from moles of solute and solvent mass in kilograms.
Mole Fraction Mixture
Computes mole fraction of each component in a two-component mixture from moles.
Dilution C1V1 equals C2V2
Solves dilution equation C1V1 = C2V2, leave the unknown as zero or negative.
Weak Acid Base pH
Estimates pH of a weak monoprotic acid using Ka*C approximation and conjugate for weak base.
pKa and pKb from Constants
Converts Ka and Kb constants to pKa and pKb and checks pKa + pKb = 14 at 25 Celsius.
Reaction Yield Percent
Computes the percent yield of a chemical reaction from actual mass and theoretical mass.
Limiting Reagent by Moles
Determines the limiting reagent in a binary reaction from available moles and stoichiometric coefficients.
Ideal Gas Volume PV nRT
Computes volume V of an ideal gas from n, T (K) and P (atm) via PV = nRT.
Solution Density Mass Volume
Computes solution density in g/mL from total mass and total volume of the sample.
Lab Solution Osmolarity
Computes osmolarity (osmol/L) from molarity and number of dissociated particles per mole.
Isotope Half Life Time
Computes remaining mass of a radioactive isotope after N half-lives using decay law.
Reaction Rate Arrhenius
Computes the rate constant k of a reaction via Arrhenius equation given A, Ea and T.
Numeric Function Derivative
Computes numeric derivative of a math expression at a point using central difference method.
Numeric Function Integral
Computes a definite integral over an interval using composite Simpson 1 3 rule.
Numeric Function Limit
Computes numeric two-sided limit of a function as x approaches a value.
Matrix 3x3 Determinant
Computes the determinant of a 3x3 matrix from its 9 inline elements.
Matrix 2x2 Inverse
Computes the inverse of a 2x2 matrix from its 4 elements a, b, c and d when det is non zero.
Matrix 2x2 Determinant
Computes the determinant of a 2x2 matrix from its 4 inline elements a, b, c and d.
Matrix Trace
Computes the trace (main diagonal sum) of a square matrix of any order entered inline.
3D Vector Norm
Computes the Euclidean norm of a 3D vector from its x, y and z components.
3D Cross Product
Computes the cross product of two vectors in R3 from their components in a single line.
3D Dot Product
Computes the dot product of two vectors in R3 from their components in a single line.
3D Points Distance
Computes the Euclidean distance between two points in 3D space from their coordinates.
Plane Equation by 3 Points
Computes the general plane equation a x + b y + c z + d equal to zero from 3 non collinear points.
Star Apparent Magnitude Calculator
Calculates apparent magnitude of a star from observed flux versus reference flux using the Pogson logarithmic scale.
Star Absolute Magnitude Calculator
Converts apparent magnitude to absolute magnitude given the distance in parsecs via the distance modulus formula.