Free tools. Small games. Plain writing about money.
All of it free, all of it running inside your browser. No sign up, no email, nothing you type is stored or sent anywhere. Start wherever you like.
Work out a number.
Built for India, in rupees, using the formulas banks and the tax department actually use. Every one explains the maths behind it.
EMI Calculator
Your monthly instalment, and the total interest a loan will really cost.
GST Calculator
Add GST, take it back out of an inclusive price, split CGST and SGST.
Income Tax
New regime against old, side by side, so you can see which one wins.
SIP Calculator
What a monthly investment grows into, and how much of it is your own money.
Invoice Generator
A GST invoice with every required field. Print it or save as PDF.
QR Code Generator
Links, UPI payments and WiFi. Download as an image, never expires.
Percentage Calculator
Increases, decreases and the difference between two numbers.
Age Calculator
Exact age in years, months and days, and the next birthday.
Waste ten minutes.
Small games that load in about a second and work the same on a phone as on a laptop. Nothing to download, no account.
2048
Slide the tiles, match the numbers, try to reach 2048.
Snake
The one everyone played on a Nokia. Try not to eat yourself.
Reaction Test
Wait for green, then tap. Find out how fast you actually are.
Memory Match
Flip the cards and find every pair in as few moves as you can.
Quick Maths
Sixty seconds of mental arithmetic. Harder than it sounds.
Stack
Time your taps to build the tower. One tap, surprisingly hard.
Read something useful.
One question per article, answered with real numbers, in the words you would use out loud.
How GST is actually calculated
Adding it is easy. Taking it back out of a price is where almost everyone slips.
6 min read MoneyWhat your loan really costs
Why a longer tenure feels cheaper every month and costs far more overall.
5 min read TaxIncome tax for freelancers in India
Presumptive taxation, what you can really claim, and the deadlines that catch people.
7 min readComing: Life OS
An Android app that keeps your tasks, notes, money, reminders and documents in one place, with an assistant that runs on the phone itself rather than in someone else's data centre. It works with the network off, because nothing needs to leave the device.
It is built and running on real phones, and it needs twelve testers for a fortnight before it can reach the Play Store. If you have an Android phone and a little patience, read what it does and put your name down.
Who made all this
I am Khanjan Kavani. I build software in Surat, and everything above is free because I needed most of it myself and got tired of sites that wanted my phone number before telling me what an EMI was.
The day job is building custom software for businesses that have outgrown a spreadsheet. If that is you, there are five working demos and honest prices on the client work page. If it is not, ignore that entirely and enjoy the calculators.
Found a mistake in something? Tell me at hello@khanjankavani.com and I will fix it, usually the same week. More about me if you are curious.