Articles
Guides and explainers that go with the tools: how the formats work, which trade-offs matter, and when to reach for one approach over another.
- 4 min read
How Long Would It Take to Crack My Password?
The charts promising three billion years assume things that are rarely true. What the number actually depends on, and how to read any estimate you are given.
- 2 min read
How to Find the Original Price Before a Discount
Divide, do not multiply. Why adding the percentage back gives the wrong answer, the formula that works, and how to check a sale price is what it claims.
- 4 min read
Is It Safe to Use an Online Password Generator?
It turns on one thing: whether the password is made on your device or on a server. How to check that for yourself, and when to use something else instead.
- 3 min read
Percentage Points Are Not Percent
A rate going from 2% to 3% rose by one percentage point and by fifty percent. Both are true, and confusing them is how numbers get misreported.
- 3 min read
What Does Lorem Ipsum Actually Mean?
It is mangled Latin from a Roman philosophy text about pain and pleasure — and "lorem" is not a word at all. Where it came from and what it says.
- 3 min read
camelCase, snake_case or kebab-case: Which Goes Where
Naming conventions are not preferences. Each language and format has one the tooling expects, and going against it costs more than it looks.
- 3 min read
encodeURI or encodeURIComponent? One Rule That Works
The two differ by eleven characters, and picking wrong either breaks the URL or corrupts the value. Here is the rule, and the plus-sign trap.
- 3 min read
Favicon Sizes You Actually Need
Generators offer dozens of sizes and almost nobody needs them all. Which files earn their place, which link tags matter, and why 16px decides it.
- 3 min read
How Much Can You Compress an Image Before It Shows?
The quality number is not a percentage of anything. What the artefacts look like, where they appear first, and how to find your own limit.
- 3 min read
PNG, JPEG or WebP: Which One, and Why
Three formats, one decision, and it hinges on what the image contains rather than on which format is newest. A rule and its exceptions.
- 3 min read
Regex Find and Replace: Five Patterns Worth Learning
Capture groups, anchors, lazy quantifiers and character classes cover almost every real find-and-replace job. Here is each one, with the traps.
- 3 min read
SHA-256 vs MD5: Which Is Broken, and What For
MD5 and SHA-1 are broken, SHA-256 is not, and none of the three should hash a password. What each one is actually safe to do.
- 3 min read
The Five Characters That Break HTML
Only five characters need escaping in HTML, one of them must be escaped first, and the context decides what escaping even means.
- 3 min read
What Is Base64, and Why Does It Make Things Bigger?
Base64 turns binary into text that survives systems built for text. Here is how it works, why it costs exactly a third, and what it is not.
- 3 min read
What Makes a Good URL Slug
A slug is the one part of a page you cannot change cheaply. Length, hyphens, stop words and dates, and what each decision costs later.
- 3 min read
What Size Should Images on a Website Actually Be?
Dimensions are the biggest lever on image weight, and most pages ship images several times larger than anything ever displays them at.
- 3 min read
Why Designers Still Use Lorem Ipsum, and When Not To
Scrambled Latin from a Roman philosophy text is still the default placeholder. Here is what it is for, and the four cases where it misleads.
- 3 min read
Why Two Word Counters Give You Different Numbers
Hyphens, contractions, headings and footnotes are all counted differently by different tools. Which number to trust depends on who is asking.
- 3 min read
Why Your Sorted List Is in the Wrong Order
Uppercase before lowercase, item10 before item2, and accents at the end. Sorting is doing what it was told — here is what it was told.
- 2 min read
Hex, RGB, HSL or OKLCH: Which Should You Use?
Four ways to write the same colour, with different strengths. Why HSL lies about brightness, and what OKLCH fixes that the others cannot.
- 2 min read
How Long Does It Take to Double Your Money?
The rule of 72 answers it in your head, and it is accurate enough to be useful. Where it comes from, where it drifts, and what it quietly assumes.
- 2 min read
How Long Should a Password Be in 2026?
Why length beats complexity, what entropy actually measures, and how to pick a password length that will still hold up in ten years.
- 2 min read
How Much Should You Tip? What Custom Actually Says
Tipping norms differ enormously by country, and the reason is structural rather than cultural. How to work out the right amount somewhere unfamiliar.
- 2 min read
How to Calculate Percentage Change
One formula, and three places people get it wrong: which number goes on the bottom, why increases and decreases are not symmetric, and points versus percent.
- 2 min read
Is It Safe to Decode a JWT Online?
A decoder can be perfectly safe or quietly disastrous, and the difference is not visible from the page. How to tell, and what to do either way.
- 2 min read
Passphrase or Random Password: Which Should You Use?
Both can be strong, but they are strong in different ways. Where each one wins, and the mistake that makes most passphrases far weaker than they look.
- 2 min read
What Is a Unix Timestamp, and Why Does It Start in 1970?
A count of seconds since an arbitrary Tuesday. Why that date was chosen, what the format deliberately ignores, and what breaks in 2038.
- 2 min read
What Is a UUID, and When Should You Use One?
A plain explanation of what UUIDs are, where version 4 gets its randomness, and when reaching for one beats an auto-incrementing key.
- 2 min read
Why CSV Is Harder to Parse Than It Looks
Splitting on commas works until the first quoted field, and CSV has no real standard to fall back on. The cases that break naive parsers.
- 2 min read
Why Do Programmers Use Hexadecimal?
Not because it is closer to how machines work — it is not. Hex survives because of one arithmetic coincidence that makes binary readable to humans.
- 2 min read
Why Does a Longer Loan Cost So Much More?
A longer term lowers the monthly payment and raises the total by far more than it seems. Where the extra money goes, and how to see the trade clearly.
- 3 min read
Why Is My JSON Invalid? The Seven Usual Causes
Almost every JSON parse error comes from the same short list of mistakes. Here is each one, why it is tempting, and how to spot it quickly.