Guides & how-tos

Practical, no-fluff explainers on money, math and everyday calculations — each one paired with a free tool so you can try the numbers yourself.

Illustration of a padlock, shield and password dots

How Strong Is Your Password? The Math Behind Password Strength

Security · 5 min read · October 22, 2026

Illustration of a calculator, percent symbol and coins

How to Calculate a Loan Payment by Hand (and Check It With a Tool)

Finance · 6 min read · October 22, 2026

Illustration of arrows and percent symbols with bar charts

Percentage Change vs. Percentage Difference: What's the Actual Difference?

Math · 4 min read · October 22, 2026

Illustration of rulers, scales and conversion arrows

12 Unit Conversions Everyone Gets Wrong (and How to Remember Them)

Converters · 7 min read · October 22, 2026