Converting Between JSON, YAML and CSV Without Losing Data
Each format can express things the others cannot. Knowing exactly what gets lost in each direction is the difference between a clean conversion and a silent corruption.
JSON Schema Validation: A Practical Guide
Valid JSON and correct JSON are different questions. JSON Schema answers the second one, and the keywords that matter are fewer than the specification suggests.
· 3 min read
Reducing Balance vs Flat Rate: Why 10% Is Not Always 10%
A flat rate charges interest on the full original amount for the entire term, even though you have already repaid most of it. The true cost is close to double the number advertised.
· 3 min read
Loan Prepayment: How One Extra Payment Changes the Whole Schedule
Prepaying a loan does not reduce your interest proportionally. It reduces it enormously, because every rupee of principal removed stops accruing interest for the entire remaining term.
· 3 min read
Section 80C: How the ₹1.5 Lakh Deduction Really Works
One ceiling, a dozen competing instruments, and lock-in periods from three years to fifteen. What actually qualifies, what it saves you, and where people waste the allowance.
· 3 min read
Old vs New Tax Regime: Which One Actually Saves You Money
The new regime has lower rates and almost no deductions. The old one is the opposite. Which wins depends on one number, and this is how to work out yours.
· 4 min read
How to Calculate EMI (and Why Your Lender’s Number Differs)
The EMI formula in full, worked through by hand, plus the four reasons the figure your bank quotes rarely matches the one a calculator gives you.
· 4 min read
Compound vs Simple Interest: Where the Difference Comes From
Simple interest is linear, compound interest is exponential, and the gap between them is small for years and then enormous. Here is exactly when it turns.
· 4 min read
Understanding BMI: What the Number Measures, and What It Misses
BMI was designed in the 1830s to describe populations, not people. The formula, the thresholds, the known failure cases, and what to use alongside it.
· 5 min read
JSON Formatting: The Rules People Get Wrong
Trailing commas, comments, NaN, big integers and duplicate keys: five places JSON differs from what developers expect, and what the spec says.
· 5 min read
How to Read an Amortisation Schedule
A loan schedule is four columns and a few hundred rows. Knowing which row to read tells you when to refinance, when to prepay, and what a longer tenure costs.
· 3 min read
BMR and TDEE: Why Every Calculator Gives You a Different Number
Three competing equations, an activity multiplier that is mostly guesswork, and a ±15% error bar nobody mentions. What calorie calculators can tell you.
· 4 min read
How Hashing Works: MD5, SHA-1, SHA-256 and Why Two Are Broken
What a cryptographic hash guarantees, how collision attacks broke MD5 and SHA-1, and why hashing a password with SHA-256 is still the wrong choice.
· 4 min read
What Actually Makes a Password Strong
Entropy maths, why complexity rules made passwords worse, and the arithmetic behind NIST dropping mandatory rotation. With the numbers, not the folklore.
· 4 min read
Colour Contrast and WCAG: The Ratio, the Thresholds, What They Miss
How the 4.5:1 contrast ratio is calculated, why grey-on-white fails so often, and the weaknesses in the formula that APCA is meant to fix.
· 4 min read
JPEG, PNG, WebP or AVIF: Choosing an Image Format
What each format is actually good at, why PNG screenshots are enormous, when WebP loses to JPEG, and the decision tree that covers almost every real case.
· 4 min read
How PDF Compression Actually Works
A PDF is a container, and its size is almost always the images inside it. What compressors do, and why one file shrinks by 90% and another not at all.
· 4 min read
Unit Conversion Mistakes That Have Destroyed Real Things
A $327 million spacecraft, an airliner that ran out of fuel mid-flight, and the everyday conversion errors that follow the same pattern.
· 5 min read
Four Percentage Calculations People Get Wrong
Why a 50% fall needs a 100% rise to recover, why percentage points are not percentages, and how discount stacking really works.
· 4 min read
Title Tags and Meta Descriptions: What Still Matters
Google rewrites most meta descriptions and two-thirds of title tags. What they still do, the pixel limits behind truncation, and how to write ones that survive.
· 4 min read
Why We Run Everything in Your Browser
Client-side processing is a design constraint, not a marketing line. What it rules out, what it costs us, and how to verify the claim yourself in ten seconds.
· 4 min read