Clear, practical guides on the things our tools help with — word counts, data formats, everyday math, unit conversions and SEO. Every article is tied to a free tool you can use right away.
PNG for graphics, JPG for photos, WebP for the smallest web files — how to choose.
ImagesLower quality to ~70-80% and pick the right format to shrink files without visible loss.
ImagesSet a new width or height with the aspect ratio locked so the image scales cleanly.
MoneyLower monthly vs long-term savings and equity — how to decide between leasing and buying.
MoneyFinance price + tax minus down and trade-in, then apply the loan formula — with an example.
MoneyHow km allowances work, your daily driving budget, and what overage costs if you go over.
DesignHow hex and RGB work, how to convert a color code by hand, and when to use each format.
MoneyThe amortization formula, a worked example, and what actually moves your monthly payment.
DevelopersWhat Base64 is for, how it works, and why it is encoding — not encryption.
SEOWhat a slug is, why it matters for SEO, and the rules that keep URLs clean and readable.
TechHow to convert MB to GB, the 1024 vs 1000 difference, and why your storage shows less than advertised.
SecurityWhat makes a password secure, the mistakes to avoid, and the easiest way to create and manage strong passwords.
ConversionsThe formula, a mental shortcut, a conversion table, and common speed-limit conversions for driving abroad.
EverydayWork it out by hand or online, how leap years affect the count, and whether to include both endpoints.
ShoppingThe formula, a quick mental method, and why stacked discounts don’t simply add up.
MoneyThe 28/36 rule, what goes into a mortgage payment (PITI), and how to estimate what you can afford.
ConversionsThe formula, a quick mental shortcut, a conversion table, and the reference points worth memorizing.
MathPercent of a number, what percent one number is of another, and percentage change — with simple examples.
EverydayStandard tipping percentages for restaurants, delivery and services, plus how to calculate a tip fast.
HealthWhat BMI means, how it’s calculated, the weight categories, and the important limits of BMI.
ConversionsThe formula, a quick estimate, a reference table, and how to convert a height like 170 cm to feet and inches.
WritingWhat counts as a word, how to hit a word-count target, and the fastest way to check any essay or article for free.
DevelopersBeautify, minify and validate JSON, plus the most common errors that make JSON invalid and how to spot them.
MoneyWhat compound interest is, the formula behind it, why starting early matters so much, and how to project your savings.
ConversionsThe exact formula, a quick mental shortcut, a handy reference table, and why the conversion is what it is.
Local SEOHow Google's UULE parameter lets you see search results from any location — and how to use it to find local ranking gaps.
Tool Goodie is first and foremost a collection of free online tools. This blog exists to answer the questions that come up around those tools — the "how do I…", "what is…" and "why does…" that a tool alone can't explain. Each article is written to be genuinely useful on its own, and links to the relevant tool so you can put it into practice in one click. New guides are added regularly.
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