7 free tools every Indian small business should bookmark
These are the tools I reach for while building software for small businesses here. All free, none asking for your phone number, and each one solving a job that comes up more often than you would think.
Why this list is short
There are thousands of free tools online and most of them exist to collect email addresses. The seven here are the ones that come up repeatedly in actual small business work in India, and every one of them runs in your browser without an account.
Full disclosure: I built these. That is precisely why they have no sign up and no data collection, because I built them for my own use first and got tired of sites that wanted my phone number before telling me what an EMI was.
1. GST calculator
The job it does that matters: taking GST out of a price that already includes it. Almost everyone gets this wrong by multiplying the inclusive price by the rate, which always overstates the tax. You have to divide by 1 plus the rate.
₹11,800 including 18 percent GST contains ₹1,800 of tax, not ₹2,124. On a year of inclusive turnover, that error is large enough to stop a return reconciling. It also gives you the CGST and SGST split, which you need on every invoice.
2. Invoice generator
A GST invoice legally requires eleven specific fields. Most templates people download cover about seven, and the missing ones are usually place of supply, the HSN or SAC code and the reverse charge statement. When a field is missing, your buyer's input tax credit becomes vulnerable, which turns into a request for a corrected invoice.
This produces a compliant document, groups tax by rate correctly, handles the CGST and SGST split against IGST, and prints straight to PDF. Nothing is uploaded, so client details stay on your machine.
3. EMI calculator
Useful in two directions. Before you borrow, to see the total interest rather than just the instalment, which is the number lenders lead with because it is the smallest one available. And when a customer asks about payment terms, to work out what an instalment plan actually costs you.
The thing worth doing with it: compare your intended tenure against one five years shorter. On a ₹25,00,000 loan at 8.75 percent, going from 20 years to 15 costs about ₹2,893 more a month and saves about ₹8,04,745 in interest. That comparison changes more minds than any argument.
4. QR code generator
Two uses that pay for themselves immediately. A UPI payment code on your invoice, which removes friction from paying you and measurably speeds up collection. And a code for your WiFi, so visitors join without you reciting a password.
One warning worth repeating, because the fraud is common here. Scanning a UPI QR code always starts a payment from the person scanning. Nobody sending you money needs you to scan anything. Anyone who says otherwise is defrauding you.
5. Image compressor
The specific Indian use case: government and examination portals with limits like "photo must be under 50 KB". Also every product photo you upload to a marketplace, and every attachment you email.
The trick most people miss is that resizing matters far more than lowering quality. A phone photo is often 4,000 pixels wide. Nothing on the web needs that. Scaling to 1,600 pixels removes about 84 percent of the pixels before compression even starts. Most people only drag the quality slider and wonder why the file is still large.
This one runs entirely on your device, which matters when the image is a document.
6. Income tax calculator
India runs two tax regimes and the new one is the default, so doing nothing is itself a choice. Which is better depends entirely on how much you can actually deduct, and the only way to know is to run your real numbers through both.
It matters more than most people assume. A salaried person on ₹15,00,000 with ₹1,50,000 of deductions pays ₹97,500 under the new regime and ₹2,10,600 under the old. That is not a rounding difference.
Note if you have business income: switching between regimes is far more restricted than it is for salary, so it is a lasting decision rather than an annual one.
Open the income tax calculator
7. Password generator
Not obviously a business tool until you consider what a compromised business email costs. Invoice fraud, where someone reads your mail and sends your customer altered bank details, is common and expensive.
Two things matter more than complexity rules. Length, because a 20 character password beats a 10 character one with every symbol on the keyboard. And never reusing a password, because when any site is breached, attackers try those credentials everywhere else.
The passphrase option gives you something like saffron-lantern-cobalt-glacier-47, which is strong and actually typeable on a phone. Use it for the handful you must memorise, and a password manager for the rest.
Three more, briefly
- Unit converter, which includes the units that actually come up here. Bigha, guntha, gaj, tola, lakh and crore. Note that bigha varies by state and is roughly 2,529 square metres in Gujarat but about 1,337 in West Bengal, so take the number from the local revenue record for anything that matters.
- Date calculator, for payment terms, notice periods and the statutory deadlines that are expressed as a number of days from an event.
- Percentage calculator, for margins and discounts. Worth knowing that two successive 20 percent discounts are 36 percent off, not 40, because percentages applied in sequence multiply rather than add.
What they have in common
Three things, deliberately. Everything runs in your browser, so whatever you type never reaches a server. There is no account and no usage limit. And each one explains the formula behind it, because a number you cannot verify is not much use in a business context.
The full set is on the tools page. If one gives you a figure that looks wrong, tell me at hello@khanjankavani.com and it gets corrected, usually the same week.
Common questions
Are these tools really free?
Yes. No account, no usage limit, no trial that expires. The pages carry advertising, which is what pays for the hosting. Nothing you type is collected or transmitted.
Is my data safe in these tools?
Every calculation runs in your browser using JavaScript on your own device. Loan amounts, income figures, client details on an invoice, images you compress, none of it reaches a server. You can load a page, disconnect from the internet, and most of them keep working.
Which one should I bookmark first?
If you are GST registered, the invoice generator and GST calculator, because you will use them weekly. If you are considering a loan, the EMI calculator before you talk to a bank rather than after.
Can I use these for my business officially?
The invoice generator produces a document with every field the GST rules require, so a completed and signed copy is a compliant tax invoice. Whether the rate and HSN code you entered are correct for what you sold remains your responsibility. The calculators are for information and are not a substitute for your accountant.
Do they work on a phone?
Yes, all of them are built for mobile first. The exception is the typing speed test, which will run on a phone but only gives a meaningful result on a physical keyboard.
Written by Khanjan Kavani, who builds software in Surat and writes these to answer the questions clients keep asking. Found a mistake? Tell me at hello@khanjankavani.com and I will correct the article itself.
General information, not professional advice. Rules in India change. Check anything important against the current position or a qualified professional. See the disclaimer.
Read next
How GST is actually calculated
Add it, remove it, split it into CGST and SGST.
TaxWhat a valid GST invoice must contain
Miss one field and your buyer loses their input credit.
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An honest test for when a spreadsheet quietly starts costing you.