Sizu Learn by real examples
Every idea is worked through a real-life case, with the arithmetic shown so you can follow every step.
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What every book gives you
Free calculators
Each book has calculators that do the sum instantly and show the working. Your figures stay in your browser.
Printable toolkits
Blank templates to fill in by hand, for when you would rather pencil it than type it.
Checked, and corrected in the open
If a number does not reconcile, tell us. Confirmed corrections are published, by book.
Find the book for what you want to do
31 books in six groups. Pick the group that matches your goal.
Everyday numbers, handledKeep more of your moneyEarn more, and know what it is worthSee through the numbersBuild it, make it, bake itUnderstand it first
Everyday numbers, handled
Stop guessing at the math in an ordinary day. Practice-first workbooks built on problems that actually come up.
The Everyday Math Workout
Be quick and sure with receipts, rent, tips and deals.
The Money Math Workout
Handle your paycheck, savings, debt payoff and taxes without the panic.
The Kitchen Math Workout
Scale any recipe, convert cups to grams and read a nutrition label.
The Garden Math Workout
Know how much soil, how many plants and what you will harvest.
The Work Math Workout
Price with confidence, tell markup from margin and spot a chart that bends the truth.
Keep more of your money
Read the numbers that quietly cost you, and fix them. Six short workbooks, one money question each.
The Smart Shopping Math Workout
Compare any two prices and see what a sale is really worth.
The Payslip Math Workout
Understand gross-to-net and check you were paid right.
The Household Bills Math Workout
Read any utility bill, compare tariffs and catch overcharges before you pay.
The Mortgage & Loan Math Workout
See what borrowing really costs: the monthly, the total interest, the schedule.
The Savings & Compound Interest Math Workout
Watch compound interest work and weigh the real cost of waiting.
The Budget Math Workout
Put every money number on one page and see where it all goes.
Earn more, and know what it is worth
For makers, sellers and anyone earning on the side: price for profit and decide what is worth your time.
Small-Business Math That Pays
Price for profit, find your break-even and keep more of what you earn.
Side-Hustle Math That Pays
Know your real hourly rate, skip the money traps and decide what is worth it.
See through the numbers
Read a financial statement, and catch what is hiding inside one. A beginner's detective series.
Read the Numbers
Read a P&L, balance sheet and cash flow statement in plain English.
Spot the Cooked Books
Learn the tells behind ten real collapses, so you can spot them early.
Don't Get Fooled
Turn the same eye on your own statements, invoices and deals, in twenty minutes a week.
Build it, make it, bake it
Measure first, buy once, cut once. Project books where the math gets you to a finished result.
Woodworking Math: Cut It Once
Build a sideboard from one sheet of plywood with cut lists that account for the blade.
Maker Electronics Math
Size a battery-powered sensor to last a year before you build it.
Vegan Baking & Pastry Math
Scale, weigh and time a bake from formulas you can trust: baker's percentage, hydration, lamination.
Home Renovation Math: Measure the Room, Not the Guess
Measure, order and cost a whole room, and check it against a builder's quote.
Walls That Stand
Count, set out, pour and lay a garden wall, or plan a low flood wall properly.
Fences That Stand Straight
Space the posts, set the line and hang a gate that stays square, even on a slope.
Understand it first
Read, don't drill. Each one explains an idea from the start in plain English, with worked examples and free calculators, and points you to the workbooks when you want practice.
Math Didn’t Have to Be This Hard
The thinking tools nobody taught you, with no exercises to dread.
Logic Didn’t Have to Be This Hard
Clear thinking for everyday life, so you can explain why you are right.
Money Didn’t Have to Be This Hard
The simple sums behind prices, pay, bills, loans and savings.
Statistics Didn’t Have to Be This Hard
Make sense of averages, polls, p-values and correlation.
Business Numbers Didn’t Have to Be This Hard
Follow margins, break-even, cash flow and the profit and loss.
Chance Didn’t Have to Be This Hard
Judge coincidences, odds, streaks, insurance and risk.
Fractions, Decimals and Percentages Didn’t Have to Be This Hard
Finally see why the rules work, and do them in your head.
Your Kid’s Math Homework Didn’t Have to Be This Hard
Help with homework by understanding the methods your child brings home.
Estimation Didn’t Have to Be This Hard
Know in a minute whether a number makes sense before you trust it.
Not sure where to start?
Begin with The Everyday Math Workout for general confidence, or open the free calculators and try one on a number from your own life. Every book page lists its chapters, calculators and printable toolkit.