Plain-English guides on personal finance, tax, property and more — with free tools to put the knowledge into action.
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Years to clear, total repaid vs borrowed, and write-off outcomes for Plan 1, 2, 4 and 5 — simulated for every salary. You need ~£57k to ever clear a typical Plan 2 loan.
Borrowing power, monthly payments and the % of take-home pay a maximum mortgage really eats — computed for every salary from £20k to £150k, with a 7% stress test.
Earning on the side? Learn when the £1,000 trading allowance runs out, the 5 October registration deadline, how much tax you'll pay, and what HMRC sees from eBay and Vinted.
Second jobs aren't taxed at a higher rate — but the BR tax code makes it feel that way. How Income Tax and National Insurance really work across two jobs, with worked examples.
Compound interest is one of the most powerful forces in personal finance. Learn how it works, the formula behind it, and how to use it to grow your savings faster.
Rental yield is the key metric every UK landlord needs to know. Learn what counts as a good yield, how to calculate it, and which UK cities offer the best returns.
Two proven methods for paying off debt faster — the debt snowball and debt avalanche. Learn how each works, which saves more money, and which one you'll actually stick to.
IR35 is one of the most misunderstood tax rules for UK contractors. This guide explains what it is, how HMRC determines your status, and what you can do about it.
How much money do you actually need to retire comfortably in the UK? This guide covers the PLSA retirement standards, the 4% rule, and how to calculate your own target.
BMI is the most widely used health screening tool in the world. Learn how to calculate it, what the ranges mean, and where it falls short as a health measure.
Stamp Duty Land Tax (SDLT) is one of the biggest costs of buying property in England. This guide explains the current rates, thresholds, and who qualifies for relief.
Banks charge far more than they should for currency exchange. Learn how exchange rates work, where the hidden fees are, and how to get the best rate when sending money internationally.
Whether you're writing an essay, a blog post, or a job application, word count affects how your work is received. Learn the ideal word counts for every type of writing.
APR (Annual Percentage Rate) is the single most important number when comparing loans, credit cards, and mortgages. Here's what it means and how to use it.
Body fat percentage tells you more about your health than BMI alone. Learn the Navy method formula, what the healthy ranges are, and the most accurate measurement methods.
The "8 glasses a day" rule is outdated. Your actual water needs depend on your weight, activity level, and climate. Learn how to calculate your personal hydration target.
Sleep needs change across your lifetime. Learn how many hours each age group needs and how 90-minute sleep cycles affect when you should go to bed.
Learn how due dates are calculated, how pregnancy weeks are counted from the LMP, and why only 5% of babies actually arrive on their due date.
Base64 converts binary data into safe printable text for email, HTTP headers, and APIs. Learn how it works, where you'll encounter it, and why it's not encryption.
UUIDs are 128-bit identifiers used in databases, APIs, and file systems worldwide. Learn the difference between v4 and v7, how unique they really are, and when to use them.
Most passwords are dangerously weak. Learn what makes a password secure, how attackers crack them, and the best strategies — from password managers to diceware passphrases.
JSON is the universal data format for APIs and web apps. Learn the syntax rules, the most common errors, how to pretty-print vs minify, and how to work with it in every major language.
The exact conversion formulas for Celsius, Fahrenheit, and Kelvin — plus a quick mental maths shortcut and a reference table for everyday temperatures from freezing to oven heat.
Convert miles to km with the exact formula, a Fibonacci mental maths trick, running distance tables, and an explanation of why the UK still uses miles for road signs.
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