Guides
A calculator gives you a number. These articles explain what the number means, where the common mistakes are, and which decision it should actually change. Written by the GetHubApps team, and updated when the underlying advice changes rather than on a schedule.
- Money8 min read
How loan interest actually works
Why your early repayments barely touch the principal, what a 'flat rate' quote is really costing you, and how to compare two loan offers on the number that matters.
- Money7 min read
Percentages, discounts and tax: the errors that cost money
Why stacked discounts never add up, how to pull tax out of an inclusive total correctly, and why a 20% rise isn't undone by a 20% fall.
- Money8 min read
SIP vs lump sum investing: when each works best
How dollar-cost averaging shields you from bad timing, why lump-sum historically beats SIP in rising markets, and how to decide based on cash flow.
- Money9 min read
How GST works: slabs, forward vs reverse calculation, and input credit
A clear guide to GST slabs, CGST/SGST vs IGST, extracting base price from gross invoices, and how input tax credit prevents cascading taxation.
- Money8 min read
Prepaying your home loan vs investing: the math and trade-offs
Should you use spare savings to prepay a mortgage or invest in index funds? How to evaluate guaranteed returns, tax deductions, and liquidity.
- Money6 min read
How EMI is actually calculated, with a worked example
The EMI formula broken down term by term, a full worked example on a real loan amount, and why stretching the tenure can quietly cost you far more in interest.
- Money6 min read
Simple vs compound interest: the real difference, with numbers
Simple and compound interest side by side on the same principal, rate and term — the exact rupee difference, and why compounding frequency itself changes the total.
- Health6 min read
BMI explained: what the number means and when to ignore it
How BMI is calculated, where the WHO weight categories come from, a worked example, and the specific situations — muscle mass, ethnicity, age — where the number stops being useful.
- Health7 min read
How to calculate TDEE and set a safe calorie deficit
The four components of daily energy expenditure, calculating BMR with the Mifflin-St Jeor formula, and why aggressive calorie cutting stalls progress.
- Web8 min read
Image formats and compression for the web
Which format to use for photos, screenshots and logos, why resizing matters more than quality settings, and how to cut page weight without visible loss.
- Web9 min read
What actually decides whether your pages get indexed
Crawling and indexing are different things. Why robots.txt doesn't remove pages from Google, what a sitemap is really for, and the checks worth doing before you blame the algorithm.
- Security8 min read
Practical password security, without the folklore
Why length beats symbols, why scheduled password changes were abandoned, and the three habits that actually prevent account compromise.
- Design8 min read
Colour on the web: formats, contrast and getting it right in dark mode
Why HSL is easier to think in than hex, why your blue-to-yellow gradient goes grey in the middle, and what contrast ratios actually require.
- Security8 min read
Understanding JSON Web Tokens (JWT) and token security
How JWT headers, payloads and signatures fit together, why tokens are encoded rather than encrypted, and how to avoid critical authentication flaws.