ToolWrenWhat Is Base64 Encoding? A Plain-English Guide
Base64 explained simply: what it is, how it works, when to use it, and why it is encoding — not encryption. With worked examples.
How to Decode a JWT (and What Each Part Means)
A step-by-step guide to reading JSON Web Tokens: the header, payload and signature, what the standard claims mean, and how to check expiry safely.
HEX vs RGB Color Codes: What's the Difference?
HEX and RGB describe the same colours in different notations. Learn how each works, how to convert between them, and when to use HSL or alpha.
How to Calculate BMI (and What the Number Really Means)
The BMI formula explained with worked examples in metric and imperial, the standard categories, and the important limitations of BMI.
Unix Timestamps Explained (Seconds, Milliseconds and the Year 2038)
What a Unix timestamp is, why it starts in 1970, the difference between seconds and milliseconds, and what the Year 2038 problem actually is.
How to Create a Strong Password (Length Beats Complexity)
Why password length matters more than special characters, how passphrases work, and how to generate and manage strong, unique passwords.
How to Format and Validate JSON (Beautify, Minify and Fix Errors)
A practical guide to reading, beautifying, minifying and validating JSON — plus the most common syntax errors and how to fix them fast.
Compound Interest Explained (with Simple Examples)
How compound interest works, why it beats simple interest over time, the effect of compounding frequency, and how to project your savings.
Classic Ciphers Explained: Caesar, ROT13, Atbash and Vigenère
A friendly tour of the classic substitution ciphers — how Caesar, ROT13, Atbash and Vigenère work, their history, and why none are secure today.
Regex Basics for Beginners: Match, Test and Understand Patterns
A gentle introduction to regular expressions — the core syntax, common patterns, flags, and how to test your regex safely against real text.
How to Read a Cron Expression (with Examples)
Cron schedules explained field by field, with common examples, the special characters, and how to check what a cron expression actually does.
URL Encoding Explained (Percent-Encoding and When to Use It)
What URL encoding is, why spaces become %20, which characters are reserved, and how it differs from Base64 — with clear examples.
How to Calculate VAT (Add and Remove Sales Tax)
How to add VAT to a net price, remove VAT from a gross price, and work out the tax amount — with worked examples and the formulas.
How to Add or Subtract Days From a Date
Add days, weeks, months or years to any date, or subtract them to work backwards from a deadline — with worked examples and calendar gotchas.
Unicode Escapes Explained: How to Decode \uXXXX
What \uXXXX Unicode escapes are, how to decode them to text and encode text back, how \xXX and surrogate pairs work, and where you'll meet them.
Roman Numerals Explained (and How to Convert Them)
How Roman numerals work, the subtraction rule, how to convert numbers to Roman numerals and back, and why they stop at 3999.
How to Convert Time Zones (Without Getting It Wrong)
A clear guide to converting times between zones: how UTC offsets work, why daylight saving trips people up, and how to schedule across time zones.
Order of Operations Explained (BODMAS / PEMDAS)
Why 2 + 3 × 4 equals 14, not 20 — the order of operations made simple, with the BODMAS/PEMDAS rules, worked examples and common mistakes.
How Mortgage Payments Are Calculated (and How to Lower Them)
How your monthly mortgage payment is worked out, why deposit and term matter so much, and how to estimate the payment on any property price.