Saving for retirement is tricky because there are so many components to it. How much should you save by retirement age? How many years will you spend in retirement? How will Social Security benefits factor into your retirement income?

In addition, retirement saving is highly dependent on your unique situation, meaning you can't simply look at what other people your age are saving and assume you should be doing the same. This is especially true when there's not even a consensus among Americans about how much it takes to retire. While around 38% of adults say they think retirement will cost less than $250,000, according to a survey from American Advisors Group, 25% say it will cost $1 million or more.

To make sure you're saving enough to retire comfortably, there are a few questions to ask yourself before you retire.

Older couple sitting on a bench at the beach.

Image source: Getty Images.

1. How much money will you need each year in retirement?

The amount you expect to spend each year once you retire will be the basis for how much you should have saved by retirement age. It's important to get as accurate an estimate as possible because if you underestimate how much you'll be spending, you'll run out of money sooner than you'd hoped.

A common guideline is to assume you'll spend around 70% to 80% of your pre-retirement income once you retire. So if you're currently spending, say, $50,000 per year, you may spend between $35,000 and $40,000 in retirement. However, this is just a ballpark estimate, and the best way to gauge your future spending is to create a retirement budget.

With a retirement budget, you won't be able to plan every penny you'll spend, but you should try your best to at least cover the more significant costs. For example, roughly how much will Medicare cost? Are you planning any expensive vacations? The more accurate your estimate is, the better idea you'll have about how much you need to save by the time you retire.

2. Are you investing aggressively enough to reach your saving goals?

You've worked hard to save for retirement, so it makes sense to want to play it safe with your investments to lower your risk of potentially losing your money. But playing it too safe could actually be riskier financially.

If your investments aren't earning a high enough rate of return, it will be extremely challenging -- if not impossible -- to reach your savings goals. Say, for instance, you're 30 years old with a goal of saving  $700,000 by age 65. If you're earning a 7% annual return on your investments, you'd need to save around $425 per month to reach that goal. But if you were earning a 2% annual return, you'd have to save just under $1,200 per month.

Even if you start early and save consistently for decades, you'll need to save significantly more each month to reach your goals. Savings accounts, CDs, and other "less risky" accounts with lower rates of return are good for short-term financial needs, but for long-term goals, your best bet is to invest in the stock market.

Investing in the stock market can be intimidating, especially since many people are still recovering financially from the Great Recession. But by investing wisely, you can limit your risk while reaping the rewards. Index funds and mutual funds are a good investment choice, because these funds allow you to spread your money across dozens or even hundreds of different stocks. That way, you can earn solid enough returns to reach your saving goals while still being safe with your money.

3. How much will you depend on Social Security?

Social Security benefits are designed to replace roughly 40% of your pre-retirement income, and yet nearly half of single beneficiaries and one in five married couples say they depend on their benefits for at least 90% of their income in retirement.

The average Social Security check amounts to just $1,471 per month, according to the Social Security Administration, which is tough for many retirees to live on. If you're expecting your benefits to cover most or all of your expenses in retirement, you may be in for a rude awakening.

Fortunately, there's an easy way to see approximately what you'll be receiving in benefits once you begin claiming. By creating a mySocialSecurity account, you can get an estimate of your future benefits based on your real earnings, giving you an idea of what you can expect to receive. Once you know how much you'll be spending each year in retirement, as well as how much you'll be receiving in Social Security benefits, you can determine how much of your retirement income will need to come from your personal savings.

4. How will you cover long-term care costs?

When you're planning fo retirement, growing old and spending your final years in a nursing home is probably the last thing you want to think about. But 7 in 10 retirees will need long-term care at some point, according to the U.S. Department of Health and Human Services, and those who do require this type of care will need it for an average of three years.

Long-term care also isn't typically covered by Medicare, and the average semi-private room in a nursing home will cost you nearly $7,000 per month. At that rate, you'll be spending roughly $250,000 on long-term care over three years. You could pay even more in some areas. If you're not prepared for these costs, they can quickly drain your retirement fund. 

One way to plan for these costs is to enroll in long-term care insurance. The key is to sign up early, though, because if you wait until you need long-term care to enroll, you'll either face sky-high rates or be denied coverage altogether.

Long-term care insurance can be expensive, with the average 60-year-old couple paying around $3,400 per year in premiums. So you'll have to decide whether the insurance is worth the hefty price tag or if you're going to pay for long-term care out of your own pocket. Either way, it's important to factor these costs into your retirement savings plan so you're not caught off guard.

There are so many factors to consider when planning for retirement, and it can easily become overwhelming. But by asking yourself a few key questions as you're planning, you can gauge whether you're on the right track to retire comfortably.