Your credit score is a bellwether of your financial habits, but it's not the only one. There are other numbers that say a lot about you when you apply for things like a credit card, car loan or mortgage, or act as a yardstick to measure how financially healthy you are.

Here are three numbers worth paying attention to and what you can do to influence them:

Debt-to-income ratio. This is how your total monthly debt payments compare with your gross monthly income, expressed as a percentage. It is important to lenders since it shows them whether you can afford to take on more debt. It matters as much as your credit score in lending decisions.

Calculating your DTI ratio helps you see how you look to lenders and understand whether you are carrying too much debt. A ratio of 20% or below is considered financially healthy. A ratio that is from 36% to 40% and higher shows financial stress, according to the Federal Reserve and the Certified Financial Planner Board of Standards.

If your DTI is on the higher side, choose a debt-payoff strategy to whittle down what you owe. Start by tackling the debt with the highest interest rate. An alternate way to bring down debt is by paying off the smallest balance first, then rolling that payment into the next small balance, a method known as the debt snowball.

Emergency fund. This is the pool of money you set aside for unexpected expenses, like a flat tire or a sudden trip to the vet.

Your job stability influences how much you should save in your fund. To start with, saving $500 should cover many common emergencies.

Retirement contribution. The emergency fund is short-term savings, while retirement contributions are for the long term. Having both matters for your financial health. Don't lump retirement contributions in with setting money aside for large expenses.

How much you should save for retirement depends on a few factors, such as your current income and lifestyle preferences. Financial experts recommend ideally saving 10% to 15% of your income each year, but to find the right number for your situation, use a retirement calculator.

If your workplace has a retirement savings plan and offers an employer match, contribute at least enough to get the full match. If you don't have a workplace-sponsored retirement account, consider opening an individual retirement account, or IRA.

The sooner you put money into a retirement account, the longer it has to grow.

Amrita Jayakumar is a writer at NerdWallet. E-mail: ajayakumar@nerdwallet.com. Twitter: @ajbombay.