Blog
Practical notes on the things our tools help with.
How to calculate concrete: cement, sand and aggregate for a slab
Wet volume, the 1.54 dry volume factor, and how a mix ratio becomes an actual number of cement bags — worked through for a 10 × 10 foot slab.
How to resize images without wrecking them
Pixels, file size and DPI are three different things. What each one means, how to keep an image sharp, and the sizes each platform actually wants.
How to reduce PDF file size, and what actually works
Why some PDFs shrink by 60% and others barely move, the four methods that genuinely reduce size, and how to hit an email attachment limit.
How to calculate BMI — and what it does not tell you
The formula in metric and imperial, the standard bands, why the thresholds differ in India, and the measurement that tracks health risk better.
How to calculate EMI, and where the interest actually goes
The formula behind every loan repayment, a worked example on a ₹50 lakh home loan, and why your early instalments barely touch the principal.
How SIP returns are calculated
Each instalment compounds for a different length of time. The formula, a worked example, and why the total is so much larger than the sum of what you put in.
Old vs new tax regime: which one actually costs you less
The choice comes down to one number — how much you genuinely claim in deductions. Here is the break-even point at several income levels.
How to calculate income tax in India, step by step
The five steps from gross salary to tax payable — deductions, slabs, the section 87A rebate and cess — worked through with real numbers for FY 2025-26.
The resume checks that actually change the outcome
What a resume score is weighted on, which fixes buy the most points, and when a good-looking template is quietly working against you.
How to read a speed test result
Ping, jitter, download and upload — what each number measures, how it is measured, and why you rarely see the figure on your bill.
What PDF compression actually does to your file
Why a text PDF barely shrinks, why a scan needs a different approach entirely, and what merge and split do to the pages in between.
SQL formatting conventions that survive code review
Leading commas, one join per line, and why your diff quality depends on your layout.
How to compress images without visibly losing quality
Picking a format, choosing a quality level, and knowing when PNG is the wrong answer.
GST calculation: inclusive vs exclusive, explained
How to add GST, back it out of a gross price, and split CGST/SGST correctly on an invoice.
Five JWT mistakes that break production
Algorithm confusion, missing expiry, and the claims everyone forgets to validate.
Why client-side tools are safer for your data
Every FreePanda tool runs in your browser. Here is what that actually means for tokens, invoices and customer data.