Car Affordability Calculator (20/4/10 Rule)
How much car you can really afford using the 20/4/10 rule — 20% down, 4-year loan, 10% of income.
Result
How to use
- 1
Enter your gross monthly income and the down payment you have saved.
- 2
Set the loan rate, monthly running cost and the price of the car you are considering.
- 3
See the most you should spend and whether your chosen car passes each part of the rule.
Questions
What is the 20/4/10 rule?
Pay at least 20% of the on-road price as down payment, take a loan for no more than 4 years, and keep the EMI plus running costs (fuel, insurance, maintenance) within 10% of your gross monthly income.
Is the 20/4/10 rule too strict for India?
It is conservative on purpose: cars lose value quickly, so a big down payment and short loan stop you owing more than the car is worth. If you stretch it, keep total car costs under 15% of income and avoid tenures longer than 5 years.
Should I use ex-showroom or on-road price?
On-road price — it includes registration, road tax and insurance, which you have to pay too.
About this Car Affordability tool
Car Affordability Calculator (20/4/10 Rule) — How much car you can really afford using the 20/4/10 rule — 20% down, 4-year loan, 10% of income. It is one of 200 free tools on namasivayam.in, made by software engineer Namasivayam Vadivelan for everyday use in India.
Everything is calculated instantly in your browser: nothing you type or upload is sent to any server, there is no sign-up, and it works on mobile and desktop. Enter your gross monthly income and the down payment you have saved.
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Results are estimates to help you plan. They are not financial, tax or medical advice.