Tesla reported a decline in quarterly profit Wednesday as the company sold more electric cars but made less money on each sale.

Net profit in the second quarter was $1.1 billion, Tesla said, compared with $1.2 billion a year earlier. Sales rose sharply to $28.2 billion, compared with $22.5 billion. Analysts had expected sales of $27.6 billion and profit of $1.3 billion, according to estimates compiled by the company.

Tesla also reported big jumps in operating expenses and capital expenditures as it poured money into new technologies, like self-driving taxis, that do not yet generate significant revenue. Tesla is also investing in factories to make batteries, semi trucks and other products.

Very few automakers have reported large increases in profit recently. Overall sales are growing slowly, partly because of tariffs and the war in Iran, and established manufacturers are struggling to compete with fast-growing Chinese companies like BYD and Geely Auto that are pushing into Europe, Latin America and many Asian countries.

General Motors said Tuesday that its second-quarter profit fell 30 percent from a year earlier to $1.3 billion, though the company said it had earned more per vehicle.

Tesla reported this month that car sales were stronger than analysts had expected, largely because increases in Europe more than made up for declines in the United States.

That should have been a good omen for profits. But the impact was muted because Tesla cut prices, offering cheaper versions of its Model Y and Model 3 vehicles as well as car loans at discounted rates.

Car sales account for more than 70 percent of Tesla’s revenue, but investors are more focused on the company’s efforts to develop self-driving taxis and robots with humanlike form. Tesla’s $1.2 trillion stock market value, many times the value of any other carmaker, is predicated on the success of those products.

There are signs that investors are getting impatient after Elon Musk, Tesla’s chief executive, failed to deliver on promises that its Robotaxi service would be widely deployed by now. The company has a relatively small number of taxis operating in Texas, California and Florida, and some of them still have Tesla employees or contractors at the wheel.

In California, Tesla does not have a permit to offer fully autonomous, paid rides, according to the state’s Public Utilities Commission, which regulates ride-hailing services. In Texas, Tesla is authorized to operate 69 self-driving taxis, according to the Department of Motor Vehicles.

Waymo, a division of Alphabet, Google’s parent company, offers driverless taxi service in 11 U.S. cities, including Atlanta, Houston and Los Angeles. Waymo has permits for 628 autonomous vehicles in Texas.

“The rhetoric makes it sounds like they are pioneering this business,” Michael Lenox, interim dean of the Darden School of Business at the University of Virginia, said of Tesla. “But they are way behind Waymo.”

Tesla shares have fallen 14 percent this year even as the Nasdaq Composite index has risen 11 percent.

“People are definitely bothered” by the slowness of the Robotaxi rollout, said Tom Narayan, lead autos analyst at RBC Capital Markets.

But he added that many investors wanted Tesla to proceed cautiously. If the company perfects the technology without needing major hardware upgrades, millions of Teslas already on the roads will be able to function as autonomous taxis, allowing the company to quickly overtake competitors.

“Maybe it’s a slow initial rollout,” Mr. Narayan said. “But if it’s successful, any Tesla could theoretically be a Robotaxi.”

During a conference call on Wednesday to discuss the company’s financial results, Mr. Musk acknowledged that an accident would be a serious setback to his Robotaxi ambitions. “If we injure even one person it will be worldwide headline news,” he said.

Despite questions about the safety of Tesla’s self-driving technology, the number of Tesla owners paying for its driver-assistance system increased more than 50 percent, to 1.5 million. A subscription to the software costs $99 a month in the United States.

Tesla’s financial performance has also been overshadowed by expectations that Mr. Musk will try to merge the automaker with SpaceX, the rocket company he controls, which recently completed an initial public offering.

Mr. Musk deflected a question on that topic. “We can’t talk about combining companies on an earnings call,” he said, while also mentioning that Tesla and SpaceX already collaborate in areas like artificial intelligence and satellite internet.

Alphabet, Google’s parent company, said on Wednesday that its investments in artificial intelligence were paying off and driving growth across its businesses, amid broader questions about whether tech companies’ enormous spending on the powerful technology can be justified.

The Silicon Valley giant, which has shelled out billions to develop cutting-edge A.I. models and to build data centers that provide the computing power for the technology, said revenue for the three months that ended in June totaled $119.8 billion, up 24 percent from a year earlier. In particular, Google’s cloud business, which lets companies rent computing power and A.I. tools, surged 82 percent to $24.8 billion.

Profit rose to $112.1 billion, quadrupling from $28.2 billion a year earlier, boosted by major investments that Google has made in recent years in other A.I.-related companies like SpaceX and Anthropic. Gains tied to those investments were valued at about $99 billion, Google said, and contributed $77 billion to overall profit, especially with SpaceX going public in June.

Google also said it would spend more than it previously predicted to build data centers and other technologies for A.I. development. It estimated that spending would hit $195 billion to $205 billion this year, more than double the $85 billion last year and up from an earlier projection of $190 billion.

“Our A.I. investments are redefining what’s possible across every part of our business,” Sundar Pichai, Alphabet’s chief executive, said in a statement.

The results exceeded Wall Street’s projections of $116.5 billion in revenue and profit of $35 billion.

Google has been racing to lead in A.I. as the technology transforms jobs, workplaces and the company’s own internet search business. To compete with rivals such as OpenAI and Anthropic, Google said in June that it was raising $80 billion to fund its data center projects by selling its stock, before raising its overall spending forecast on Wednesday.

Some have questioned whether such spending is excessive. Last week, stock markets fell because of concerns about increasing A.I. competition from China after a Chinese start-up, Moonshot AI, released an A.I. technology that was nearly as powerful as the leading American model, Claude Fable 5 from Anthropic.

So far, A.I. has been a boon to Google’s business. The company has melded A.I. into search, with its Gemini chatbot generating answers and users assigning A.I. “agents,” or bots, to run continuous searches on their behalf. Advertisers on YouTube have new A.I. tools, and viewers have A.I.-curated video recommendations. And companies are clamoring to use Google’s cloud computing services to run their A.I. projects.

Google is “one of the best positioned A.I. companies around,” said Brian Nowak, an analyst at Morgan Stanley.

Demand for Google’s A.I. services has become so intense that the company cannot keep up. Google said its cloud business had a backlog of potential contracts totaling $514 billion, up from $106 billion a year ago. Over half of that backlog will be worked through over the next two years, said Anat Ashkenazi, Google’s chief financial officer.

Revenue for Google’s advertising business rose 14.4 percent to $81.6 billion in the quarter as users flocked to YouTube and search.

In May, the company expanded its A.I. offerings in search, overhauling its iconic search bar for the first time in 25 years with new A.I. tools and adding the ability for people to assign continuous searches to A.I. agents that can act autonomously to function like digital personal assistants. The infusion of A.I. has attracted users, the company said, with its AI Mode chatbot-style search feature reaching one billion monthly active users.

Google’s subscription business, which includes users who pay for YouTube services and those who pay to use Google’s A.I., rose 15 percent to $12.9 billion. Gemini, the company’s flagship A.I. app, hit 950 million monthly active users, and daily users tripled over the last year, Google said.

The World Cup soccer tournament also aided search and YouTube, the company said, with search getting its highest-ever use during the event and 1.7 billion people watching World Cup-related clips on YouTube. “This really highlights how much people turn to Google in moments that matter,” Mr. Pichai said.

On Tuesday, Google unveiled three A.I. models, which are intended to work more effectively and at a lower cost than previous versions. The company’s flagship model, Gemini 3.5 Pro, was set to be released in June but has not been made available. Mr. Pichai said that the Pro model remained in testing and that the company was also testing an additional model, Gemini 4.

He acknowledged that Google’s models had lagged those of rivals, particularly on coding tasks, but said he expected Gemini 4 would help the company compete.

“There are many attributes at which we are still at the frontier,” Mr. Pichai said.