With so many shares to choose from on the ASX, it can be difficult to decide which ones to buy. The good news is that brokers across the country are doing a lot of the hard work for you.

Three top ASX shares that leading brokers have named as buys this week are listed below. Here's why they are bullish on them:

According to a note out of Goldman Sachs, its analysts have retained their buy rating and $13.70 price target on this testing services company's shares. This follows news that ALS is acquiring the remaining 51% in the Nuvisan business that it does not already own for nil cost. It notes that ALS previously had a call option to acquire the remaining stake for 13x the adjusted EBITDA. In addition, the broker notes points out that ALS now expects its earnings to be at the low end of its guidance range in FY 2024. Nevertheless, it remains positive. The ALS share price is trading at $12.86 today.

A note out of UBS reveals that its analysts have upgraded this scrap metal company's shares to a buy rating with an improved price target of $14.50. The broker is feeling more positive thanks to improving scrap metal prices. And with its shares trading at a discount to book value despite these improvements, the broker feels now is the time to invest. It has also upgraded its earnings estimates to reflect higher margin assumptions. The Sims share price is fetching $12.21 this afternoon.

Another note out of UBS reveals that its analysts have retained their buy rating on this online travel agent's shares with an improved price target of $10.00. This follows the release of an update on the WebBeds business last week. The broker believes that the company is well-positioned to accelerate its growth through the use of big data and artificial intelligence. In fact, UBS believes the company can grow quicker than the market is currently pricing in. The Webjet share price is trading at $8.94 on Monday.