Here's the most straightforward high-yield savings account for no fees whatsoever and easy mobile access

Editor's Note: APYs listed in this article are up-to-date as of the time of publication. They may fluctuate (up or down) as the Fed rate changes. CNBC will update as changes are made public.

High-yield savings accounts are a great way to build up an emergency fund or grow your money for a big purchase in the near future, like a new car or a down payment on a first home, because they offer significantly greater interest rates than traditional savings accounts.

But with endless high-yield options available — from online to brick-and-mortar banks — some find it easier to go with one that is straightforward and simple to use. Marcus, the consumer banking arm of Goldman Sachs, offers a financial product that fits this description.

The Marcus by Goldman Sachs High Yield Online Savings ranked as the "best for no fees" pick on CNBC Select's top high-yield savings account list.

Below, we take a close look at the Marcus by Goldman Sachs High Yield Online Savings by breaking down its annual percentage yield (APY), access to your cash, perks and fees so you can decide if this high-yield savings account is right for you.

• APY 
• Access to your cash
• Perks
• Fees
• Bottom line

The current APY is 4.50%. There is no minimum deposit required to open a Marcus by Goldman Sachs High Yield Online Savings and users can start earning interest with just a low minimum of $1 in their account.

If you want to really maximize the higher APY, however, we recommend having more than just a dollar in your account. Shon Anderson, a certified financial planner at Anderson Financial Strategies, LLC, recommends keeping two to four months of expenses in your savings.

Marcus compounds interest on your savings daily, like the best high-yield savings accounts mostly do. The APY offered reflects the total amount of interest that the account would earn for the year.

Account holders can withdraw money from their Marcus savings account online and by phone through ACH or by free wire transfer to a linked account at another bank. You can also request a withdrawal by check mailed to you.

To add money to your account, you can transfer funds, make direct deposit payments, send a check, make a wire transfer or deposit checks via the mobile app. You cannot deposit cash into a Marcus savings account.

Marcus doesn't charge a fee if you link other bank accounts for incoming and outgoing transfers, but keep in mind that your other bank might. There is currently no limit to the number of withdrawals or transfers per statement cycle.

While there are no ATM cards or checking account options available through Marcus, the bank does offer a variety of no-fee personal loans as well.

Those savers with the Marcus account can also count on easy mobile access. The bank's new mobile banking app is simple to use and allows users to set up recurring deposits, track their savings goals and see how much interest they've earned over the year.

Though this is an online savings account, customers can receive live customer support over the phone or through online chat and the bank's U.S.-based contact center is open seven days a week.

Marcus offers no fees whatsoever: no minimum deposits and no monthly fees.

While there are no associated fees, your account can be closed if you do not fund the account within 60 days or if you have a zero balance for 60 days.

The Marcus by Goldman Sachs High Yield Online Savings is a straightforward account that guarantees customers ease of use.

Although the account doesn't come with many bells and whistles, it can help you increase your savings over time without having to worry about meeting certain requirements or keeping up with fees.

For those looking to open a high-yield savings account along with a checking account, consider instead the Ally Online Savings Account or Varo Savings Account.

To determine which high-yield savings accounts offer the best return on your money, CNBC Select analyzed dozens of U.S. savings accounts offered by online and brick-and-mortar banks, including large credit unions. We narrowed down our ranking by only considering those savings accounts that offer an above-average APY, no monthly maintenance fees and low (or no) minimum balance requirements.

While the accounts we chose in this article consistently rank as having some of the highest APY rates, we also compared each savings account on a range of features, including ease of use and account accessibility, as well as factors such as insurance policies and customer reviews when available. We also considered users' deposit options and each account's compound frequency.

All of the accounts included on this list are FDIC-insured up to $250,000. Note that the rates and fee structures for high-yield savings accounts are not guaranteed forever; they are subject to change without notice and they often fluctuate in accordance with the Fed rate. Your earnings depend on any associated fees and the balance you have in your high-yield savings account. To open an account, most banks and institutions require a deposit of new money, meaning you can't transfer money you already had in an account at that bank.