Guides & explainers
Plain-English deep-dives behind the calculators — every figure sourced and verified, each guide paired with a tool you can use. 8 guides and counting.
cm to inches: The Exact Factor (and Why Temperature Isn't a Simple Multiply)
Most unit conversions are a single multiply: pick the right factor, multiply, done. Temperature is the famous exception — and getting it wrong is one of the most common conversion mistakes there is.…
How 'Days Until' Calculators Compute Moving Holidays (Easter, Thanksgiving)
Ask a countdown tool "how many days until Christmas" and the answer is easy — Christmas is always December 25. Ask it for Easter or Thanksgiving and something more interesting has to happen behind…
GST Invoice Format 2026: The Rule-46 Mandatory Fields
A GST tax invoice is not just a bill — it is the document your buyer needs to claim input tax credit (ITC). Miss one mandatory field and the invoice is legally defective, and your customer may be…
What's Inside a JWT? Decode It, Verify It, and Avoid the alg:none Trap
You paste a token mid-incident to read one claim — is it expired? which alg? whose sub? — and a wall of eyJ... stares back. A JWT looks encrypted. It isn't. It's three base64url-encoded chunks anyone…
CGPA to Percentage: Why the Formula Depends on Your University
You Google "CGPA to percentage," land on a page that says "multiply by 9.5," and confidently write 76% on your job application. Then the transcript your university issues says something else…
A1C to Average Blood Glucose (eAG): The ADA Formula
Your lab report says your A1C is 7.0%, but your glucose meter reads in mg/dL. The two numbers measure the same thing — your average blood sugar — on different scales, and one simple equation converts…
Compound Interest: How $500 a Month Becomes $86,000 (2026)
You put $10,000 into an index fund ten years ago and never touched it. Someone else put in nothing upfront but added $500 every month. At 7% annual interest, compounded monthly, who comes out ahead?
Average Salary Hike in India 2026: Sector-by-Sector (EY & Aon)
Every April, India's corporate workforce checks two numbers: the hike percentage on their appraisal letter and how it stacks up against what the rest of the market got. In 2026, those two benchmarks…
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