Across trades

Universal tools

Maths and templates that work in every trade — and at school. Every tool shows not just the answer, but also the formula and how to work it out, with your own numbers.

Open Pythagoras →Free · no account needed

Geometry

Triangles, area, volume, circles and angles.

Pythagorasa² + b² = c²Find the missing side, set out a right angle, check whether a room is square, and find the space diagonal.Area and perimeterm²Rectangle, triangle, trapezium, circle and composite shapes — area and perimeter.Volume and surface aream³ · lBox, cylinder, cone, sphere, pyramid, prism, pipe and frustum — also in litres.The circleπRadius, circumference and area from one measurement — plus sector, annulus, chord and rise.Right trianglesin · cos · tanSine, cosine and tangent: all sides and angles from two known values.Angles180°The third angle in a triangle and the angle sum of a polygon.Points in the coordinate system(x ; y)Distance, midpoint and the line between two points — drawn in.Similar figuresk · k² · k³Scale factor and missing sides — area is multiplied by k², volume by k³.Any trianglesin A / aThe sine and cosine rules: find the rest from SSS, SAS, ASA or SSA.Transformations(x ; y) → (x′ ; y′)Reflect, rotate and translate a figure on a coordinate grid — before and after.

Numbers and percentages

Percentages, fractions, powers, roots and primes.

Percent%Percentage of, how many per cent, percentage change, discount and VAT.Fractions¾Add, subtract, multiply and divide fractions — and simplify the answer.Powers and rootsxⁿ · √Powers, square roots, nth roots and numbers as powers of 10.Primes and divisors2 · 3 · 5Is it a prime? Prime factors, divisors, GCD and LCM.Rounding and estimating≈Round to decimals, tens or significant figures — and make an estimate.Order of operations( ) ^ · +Enter a calculation and see it worked out step by step in the right order.Number systems and Roman numerals1101₂ · XIVBinary, hexadecimal and Roman numerals — converted both ways with working.

Equations and functions

Solve equations, draw graphs and work with ratios.

Equationsx = ?Solve equations and inequalities step by step — and isolate a quantity in a formula.Formula with three quantitiesA = B · CThe formula triangle: find the third quantity in A = B · C — e.g. U = R · I.Functionsf(x)Quadratic function, inverse proportionality and power function — with a graph.Linear functiony = ax + by = ax + b as a graph and table — the line through two points or the line of best fit.Scale and ratios1 : 50From drawing to reality, area and volume to scale, the rule of three and dividing in a ratio.Two equations with two unknownsx ; ySolve a system of equations step by step and see the intersection on the graph.Growth and decayy = b · aˣPercentage growth, the growth rate from two measurements, and doubling time.

Measurements and units

Convert units, calculate with the clock, and find speed, time and distance.

Unit convertermm ↔ mFrom mm to km, Pa to bar and kB to GB — with the unit staircase.Speed, time and distances = v · tFind the third when you know two of speed, time and distance.Time calculations and the clockt : minTime between two clock times, add time, and 1.75 h = 1 h 45 min for the timesheet.

Workshop maths

Slope, material consumption with waste, mixing ratios, weight and unit price.

Slope and fall% · ° · 1:xFall from level to level, in per cent, per mille, degrees and mm per metre — and the height difference.Material consumption including wastem² + %Boards, paint, battens at c/c spacing and packs — for a composite surface or a whole room, with waste.Mix ratio1 : x1 : 50, three parts, percent, dilution and the cross rule — how much of each.Density and weightρ = m / VThe weight of plates, bars and pipes — per piece, per running metre and in total.Unit pricekr. pr.Compare offers on price per kg, litre, metre or piece.

Finance and money

Costing and markup, interest and savings, loans and payback periods — with your own numbers.

Pay after tax% → kr.Play with your pay: what is left once the labour market contribution and tax are deducted?Costing and markup% · kr.From cost price to selling price with markup or gross margin — and VAT last.Interest and savingsK = K₀(1+r)ⁿCompound interest with a fixed deposit every month, quarter or year.Loans and savingsy · H · nAnnuity and serial loans: payment, remaining debt and interest period by period.Energy and paybackI / BWhen has an investment paid for itself? With your own saving and price.

Statistics and probability

Mean, median, probability and charts from your own numbers.

Statisticsx̄Mean, median, quartiles, box plot and standard deviation — with a frequency table.Grouped dataQ₁ · m · Q₃Intervals and frequencies: histogram, cumulative curve and quartiles read off the curve.ProbabilityP = g / mDice, coins, combinatorics and two draws with a tree diagram — «and» and «or».Charts▮ ◔Bar, stick, pie, line and scatter charts from your own numbers — ready to print.

Printable templates

Paper, coordinate system, number line, times table, hundred square, clock, ruler and protractor.

Printable paperA4Squared paper, graph paper, isometric paper and dot paper in A4.Coordinate systemA4An empty coordinate system with the axes you choose — ready to print.Number lineA4A number line from any number — whole numbers, decimals or fractions.Times table1–20The small and the large table to print — and a practice track with your record.Hundred square1–100The numbers from 1 to 100 — filled in, blank or with a times table coloured in.Clock and time12 · 24Set the clock, and print worksheets with clocks to read or draw.Printable ruler1:1 · 1:50Rulers at 1:1 and scale rulers at 1:20, 1:50 and 1:100 — and read a measurement on the drawing.Protractor0–180°A 1:1 protractor to print and cut out.Formula sheetA4The most important formulas for area, volume, percentages and triangles on one sheet.

Music

The guitar's scales, chords and keys with sound — and build your own song from the chords.

The Fretboard — guitar♪ Am · G7All scales and chord voicings with sound, the circle of fifths, find the chord you're playing, and build your own song.

For the company

Discebo's own tools for hours, jobs, quotes and prices — and the education programmes' finance calculators. Most require you to be logged in.

Company finances
Job costing with contribution margin per job, quotes, invoices, VAT, price list and rates — in your company's hub.
Timesheet
Log hours on jobs, see the week's total and send them for approval.
Fleet economy
What each vehicle costs in depreciation, leasing, fuel and servicing — and which is cheapest per km.
My finances
Your own deductions, rates and earnings — not the company's.
Discebo for companies
What the company section can do, and how to get started.