The S&P 500 and Nasdaq edged up to fresh records on Thursday while the Dow retreated following a mixed round of corporate earnings that lifted Google parent Alphabet but battered Tesla.

The Nasdaq led major indices, finishing 0.2 percent higher at 21,057, a new record.

The S&P 500 added 0.1 percent at 6,363, also a record, while the Dow Jones dropped 0.7 percent to 44,693.

Alphabet climbed 0.9 percent after reporting US$28.2 billion in quarterly profits as it touted new artificial intelligence investments.

But Tesla slid 8.2 percent as CEO Elon Musk warned of a rough patch for earnings following the elimination of a federal tax credit for electric vehicles.

While earnings have taken centre stage for much of the week, stocks have also been buoyed by US President Donald Trump's trade deal with Japan and hopes for more agreements.

"Buyers are in control and there remains a lot of optimism about future trade deals," said Adam Sarhan of 50 Park Investments.

"For now the market is choosing to look at the bullish side of the coin," he said. "Not the bearish side and not the neutral side."

But the Dow was weighed down by a 7.6 percent drop in IBM and a 6.2 percent fall in Honeywell International following earnings reports.

Another Dow member, UnitedHealth International, fell 4.8 percent after it disclosed that it was cooperating with US Department of Justice criminal and civil probes into the company's billing practices.

Union Pacific fell 4.5 percent as it disclosed that it was in talks with fellow freight rail company Norfolk Southern on a possible merger. (AFP)