Free study tools for students

LCM calculator

Lowest common multiple of 2 to 10 numbers, with prime factors, a Venn diagram and every step.

HCF / GCF calculator

Highest common factor (greatest common factor) of 2 to 10 numbers, with prime factors and a Venn diagram.

Prime factorisation

Any number as a product of primes, in index form, with its factor tree drawn for you.

Mean, median, mode, range

Mean, median, mode and range for any list of numbers, with the working explained.

Order of operations

Any calculation solved one operation at a time in BIDMAS / PEMDAS order, with exact answers.

Fraction calculator

Add, subtract, multiply and divide fractions and mixed numbers, with the method shown.

Percentage calculator

Every type of percentage question, from % of a number to reverse percentages, with the method.

Quadratic solver

Solve ax² + bx + c = 0 exactly, with the discriminant, factorised form, surds and the vertex.

Simultaneous equations

Two linear equations in x and y solved by elimination, with every step and a check.

Pythagoras calculator

The missing side of a right-angled triangle, with exact surds, decimals and the working.

Standard form

Convert to and from standard form (scientific notation), with how the decimal point moves.

Rounding calculator

Round to significant figures or decimal places, with the deciding digit explained.

Scientific calculator

Trig, logs, powers, roots, factorials and standard form, with a history you can reuse.

Graphing calculator

Plot up to five graphs, trace them, and find roots, intercepts and intersections.

Long division calculator

Long division with each step explained, as a remainder or as a decimal.

Area calculator

The area of six common 2D shapes, with the formula and working shown.

Volume calculator

The volume of eight common 3D shapes, with the formula, exact π answers and working.

Surface area calculator

Total surface area of six 3D shapes, face by face, with π answers and working.

Circle calculator

Radius, diameter, circumference and area from any one of them, with the working.

Arc length and sector area

Arc length, sector area and perimeter from the radius and angle, with the working.

Trigonometry calculator

Missing sides and angles in right-angled triangles, choosing SOH, CAH or TOA for you.

Sine rule calculator

Missing sides and angles in any triangle with the sine rule, including the ambiguous case.

Cosine rule calculator

A missing side or angle in any triangle with the cosine rule, with the working.

Gradient calculator

The gradient (slope) of the line through two points, with the working shown.

Equation of a line calculator

y = mx + c from two points, or a point and the gradient, with the working.

Midpoint calculator

The midpoint of two points, averaging each coordinate, with the working shown.

Distance between two points

The distance between two points with Pythagoras, as a decimal and an exact surd.

nth term calculator

The nth term rule of a linear or quadratic sequence, from its first few terms, with the working.

Ratio calculator

Share an amount in a ratio, or simplify a ratio, with the working shown.

Square root simplifier

Any square root in simplest surd form (a√b), with the square factor and working shown.

Recurring decimal to fraction

Any recurring decimal as a fraction in simplest form, by the algebra method, with working.

Compound interest calculator

Compound interest or depreciation with the multiplier method and a year-by-year table.

Simple interest calculator

Simple interest and the total amount, with the working shown.

Standard deviation calculator

Mean, variance and standard deviation (population and sample) with the working.

Mean from a frequency table

The mean (or estimated mean for grouped data) from a frequency table, with the fx working.

Inequality calculator

Solutions to linear and quadratic inequalities, with the working and sign flips explained.

Factorising calculator

Quadratics factorised into brackets, including a ≠ 1 and the difference of two squares, with working.

Expanding brackets calculator

Double and triple brackets multiplied out, every product listed, with like terms collected.

Completing the square calculator

a(x + p)² + q form, the turning point and exact solutions, with every step.

Upper and lower bounds

Upper and lower bounds and the error interval for rounded or truncated values, with working.

Speed, distance, time calculator

Speed, distance or time from the other two, with units converted and the working shown.

Density calculator

Density, mass or volume from the other two, in kg/m³ or g/cm³, with every step shown.

Ohm's law calculator

Voltage, current or resistance from the other two using V = IR, with units and working.

Kinetic energy calculator

Kinetic energy, mass or speed from the other two using Eₖ = ½mv², with working.

GPE calculator

Gravitational potential energy, mass, height or g from Eₚ = mgh, with every step shown.

Wave speed calculator

Wave speed, frequency or wavelength using the wave equation, with units converted.

Specific heat capacity calculator

Energy, mass, specific heat capacity or temperature change from ΔE = mcΔθ, with working.

Half-life calculator

Amount remaining, starting amount, time or half-life for radioactive decay, with working.

Relative formula mass calculator

Mr for any formula, including brackets and water of crystallisation, with a breakdown table.

Moles calculator

Moles, mass or Mr from the other two, with Mr worked out from a formula if you like.

Punnett square calculator

The Punnett square for two parents, with genotype and phenotype ratios as fractions and percentages.

Periodic table

All 118 elements with atomic masses, electron configurations, groups and properties.

Equation balancer

Balances chemical equations and shows the atom count on each side.

Acceleration calculator

Acceleration, either velocity or time from the other three, with units converted and the working shown.

Force calculator (F = ma)

Resultant force, mass or acceleration from Newton's second law, with the working shown.

Momentum calculator

Momentum, mass or velocity from p = mv, with the working and help with collisions.

Pressure calculator

Pressure, force or area from p = F ÷ A, with area units converted and the working shown.

Power calculator

Power, energy or time from P = E ÷ t, with units converted and the working shown.

Efficiency calculator

Efficiency as a percentage, or the useful or total energy or power, with the working.

Work done calculator

Work done, force or distance from W = F × s, with the working shown.

Spring constant calculator

Spring constant, force or extension from Hooke's law, with the working shown.

Moments calculator

Moment, force or distance from M = F × d, with the working and balancing moments explained.

Electrical power calculator

Power, current, potential difference or resistance with P = IV or P = I²R, with the working.

Charge calculator

Charge flow, current or time from Q = I × t, with the working shown.

Specific latent heat calculator

Energy, mass or specific latent heat for melting or boiling, with the working shown.

SUVAT calculator

Any three of displacement, velocities, acceleration and time give the other two, with working.

Series and parallel resistors

Total resistance in series or parallel, for any number of resistors, with the working.

Percentage error calculator

How far a measurement is from the accepted value, as a percentage, with the working.

Concentration calculator

Concentration in g/dm³ or mol/dm³, or the mass, moles or volume, with cm³ converted.

Percentage yield calculator

Percentage yield, actual yield or theoretical yield, with the working and reasons yields fall short.

Atom economy calculator

Atom economy from a balanced equation, with each relative formula mass worked out for you.

Empirical formula calculator

The simplest whole-number formula from masses or percentages, with the working shown.

Percentage by mass calculator

The percentage by mass of every element in a compound, from its formula, with the working.

Bond energy calculator

Overall energy change from bond energies, and whether it's exothermic or endothermic, with working.

Rf value calculator

Rf value from spot and solvent distances, or a distance from the Rf, with the working.

Magnification calculator

Magnification, image size or real size, with mm, µm and nm converted and the working shown.

Revision timetable generator

A day-by-day revision plan from your exam dates and weak subjects, ready to print or download.

SAT study plan generator

A week-by-week SAT plan from your current scores, target and test date.

Times tables quiz

Twenty questions from the tables you choose, a 6-second timed mode, and extra practice on mistakes.

Pomodoro timer

25-minute focus sessions and short breaks, with a chime, a session count and adjustable lengths.

Flashcard maker

Paste a list to make cards, then study with Leitner boxes so missed cards come back more often.

Word counter

Count words and characters, track a word limit, and see reading time and readability as you type.

Typing speed test

A 30-second, 1-minute or 2-minute typing test with live words per minute and accuracy.

Citation generator

APA and MLA references for web pages, books and journal articles, ready to copy with italics.

Mental maths game

Answer as many sums as you can in 60 seconds, at three levels, and beat your best score.

GPA calculator

Unweighted and weighted GPA on the 4.0 scale, with honors and AP/IB classes.

SAT superscore calculator

Your best Reading and Writing plus best Math across test dates, compared with your best single sitting.

National Merit calculator

Your National Merit Selection Index from your PSAT/NMSQT section scores, with the formula.

Test grade calculator

A test score as a percentage and letter grade, plus a table for every number of points lost.

Tutoring cost calculator

What tutoring costs per month and per year at your hourly rate, compared with an AI tutor.

Final grade calculator

The score you need on your final exam to reach the course grade you want.

Weighted grade calculator

Your course grade when homework, tests and exams count for different amounts.

CGPA calculator

Your CGPA from semester GPAs and credit hours, or SGPA from courses, on any scale.

CGPA to GPA converter

A CGPA on one scale as a GPA on another, a percentage and marks out of any total, with the working.

UCAS points calculator

Total UCAS Tariff points for A levels, AS, the EPQ and Scottish Highers, from UCAS's tables.

College GPA calculator

Semester GPA from letter grades and credits, and the new cumulative GPA, on the 4.0 scale.