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How does AI actually work?
Models learn statistical patterns from huge amounts of data, then predict the most useful next word, pixel or decision.
US mortgage
$2,573
estimated / month
Tonight · US
Chicken tacos
with rice and salsa
$4.40 for two
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Mortgage
Estimate monthly payments, taxes, insurance, PMI and extra-payment savings with a full amortization schedule.
Open toolAuto loan
Work out a car payment from price, down payment, trade-in, tax, fees, APR and term, with a full schedule.
Open toolPercentage
Work out a percentage of a number, compare two numbers, measure change, or add a markup or discount.
Open toolMeal planner
Plan a week of American favorites or a lower-carb diabetic-friendly week, scale servings, and generate a categorized grocery list with cost estimates.
Open toolPDF workshop
Merge, split, reorder and rotate PDFs, extract exact page ranges, or turn images into a PDF — entirely in your browser.
Open toolUnit converter
Convert length, weight, temperature, volume, area, speed, time, energy, pressure and data in US and metric units.
Open tool26 tools across finance, health, documents, dates and everyday utilities.
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Short explainers built for people who want the useful version first.
Technology
Plain-English explainers on software, the internet and the systems shaping daily life.
4 articlesBrowseScience
Clear answers to everyday science questions, from biology and physics to the climate.
3 articlesBrowseGuides
Practical, step-by-step guides for money, food, documents and digital life.
4 articlesBrowsePersonal Finance
Compound interest, credit, saving and the money decisions that add up over time.
2 articlesBrowseHome & Housing
Renting, buying, mortgages and the costs that come with a place to live.
1 articleBrowseAI
Large language models, chatbots and agents explained without the hype or the maths degree.
2 articlesBrowseDocuments
PDFs, scans, OCR and file formats — with practical ways to keep documents private.
2 articlesBrowseHealth & Fitness
Calories, body composition and fitness measures explained with their limits.
2 articlesBrowseFood
Protein, meal prep, shopping and realistic ways to eat well on a budget.
2 articlesBrowseEveryday Math
Fractions, ratios, percentages and the arithmetic that shows up in daily life.
2 articlesBrowseReference desk
The context behind the tools.
Definitions and side-by-side comparisons, so the result makes sense.
Start here
A good place to begin
Our most useful explainers, picked for first-time visitors.
Mortgage basics: what you are actually paying for
A practical guide to PITI, amortization, PMI, escrow and the difference between pre-qualification and pre-approval in the US.
Why is the sky blue?
The real reason is not the ocean or the ozone layer — it is how air scatters different colours of sunlight.
How does AI actually work?
A plain-English guide to machine learning, neural networks and large language models — what they do, how they learn, and where they go wrong.
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Explainers written for real decisions, with clear limits and no false certainty.
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