Articles
Short, practical guides related to the tools on this site.
How Loan Amortization Actually Works
Where your early payments go, and why overpaying at the start saves the most interest.
August 6, 2026Calories and Macros: The Numbers That Actually Matter
How BMR, TDEE and macro splits fit together, and what the formulas can and cannot tell you.
August 5, 2026Reading Broken JSON: Formatting and Validation Basics
The most common JSON syntax errors, and how a formatter helps you find them fast.
August 5, 2026VAT and Sales Tax: Adding, Removing and Getting It Right
Why removing VAT is not the same as subtracting the rate, with the correct formulas.
August 4, 2026A Practical Guide to Metric and Imperial Conversion
The handful of conversion factors worth memorising, and where rounding gets you in trouble.
August 3, 2026How to Compress Images Without Obvious Quality Loss
Picking the right format and quality setting to cut image weight by half or more.
August 2, 2026How to Merge and Split PDFs Without Uploading Them
Combine, split and reorder PDF files entirely in your browser, so nothing leaves your device.
August 1, 2026Compound Interest, Explained With Real Numbers
How compounding frequency and time horizon change your final balance, with worked examples.
July 20, 2026How BMI Is Actually Calculated (And Its Limits)
A quick look at the formula behind Body Mass Index, and why it does not tell the whole story.
July 15, 2026What Actually Makes a Password Strong
Length beats complexity. Here is why, and what to do about it.