There are a lot of exchange-traded funds (ETFs) to choose from on the Australian share market.

So many, it can be hard to decide which ones to buy with your $500.

To narrow things down, let's take a look at four ASX ETFs that could be excellent options for Aussie investors right now. They are as follows:

Betashares Global Cash Flow Kings ETF (ASX: CFLO)

The first ASX ETF that could be a top pick is the Betashares Global Cash Flow Kings ETF. The fund manager, Betashares, notes that companies generating high levels of free cash flow have traditionally outperformed the market over the medium to long term. This ETF focuses on global companies with strong free cash flow and includes giants such as Alphabet (NASDAQ: GOOG) and Visa (NYSE: V). It is no wonder then that Betashares recommended the ETF as one to buy this year.

BetaShares Global Cybersecurity ETF (ASX: HACK)

Another top ASX ETF that could be a buy is the BetaShares Global Cybersecurity ETF. As you might have guessed from its name, it provides investors with access to the leading players in the global cybersecurity industry. Betashares highlights that "an estimate of the total addressable market by McKinsey suggests that the cybersecurity market is $1.5-$2.0 trillion globally, and at best only 10% penetrated with a very long runway for growth." In light of this positive outlook, it could make this ETF a great option for a long term investment.

iShares S&P 500 ETF (ASX: IVV)

A third ASX ETF that could be a top option for a $500 investment is the iShares S&P 500 ETF. It allows investors to buy the 500 largest listed companies on Wall Street. This means that you will be buying a slice of companies from a range of different industries and sectors. This includes giants such as Amazon, Apple, Broadcom, Costco, Microsoft, and Walmart.

BetaShares Crypto Innovators ETF (ASX: CRYP)

A final ASX ETF to consider for a $500 investment is the BetaShares Crypto Innovators ETF. If you think cryptocurrencies are the future then this one could be for you. That's because the BetaShares Crypto Innovators ETF allows your to gain exposure to the crypto market without having to buy coins. This fund provides investors with access to the leading players in the industry. This includes pure-play crypto companies, as well as those whose balance sheets are held at least 75% in crypto-assets. If the crypto market continues to grow over the long term, these companies stand to benefit greatly.