Trump had yet to concede defeat, but Western and Asian allies expressed hoped for a fresh start following Trump's "American First" trade policies, withdrawal from the Paris climate agreement and attacks on NATO and the World Health Organization.
In Asia, a region on edge about the strategic ambitions of China's ruling Communist Party, the elected leaders of Japan, South Korea and Taiwan invoked "shared values" with Washington and expressed hope for close relations.
"I look forward to working with you to further strengthen the Japan-US Alliance and ensure peace, freedom, and prosperity in the Indo-Pacific region and beyond," said Japanese Prime Minister Yoshihide Suga on Twitter. President Moon Jae-in of South Korea said he looked forward to working together "for our shared values."
Word of the victory in Pennsylvania that pushed Barack Obama's former vice president past the threshold of the 270 Electoral College votes needed to take over the Oval Office spread around the globe, sparking celebrations.
There was no immediate official reaction from Beijing, which is mired in conflicts with the Trump administration over trade, security and technology. But Chinese social media users welcomed the change. A post on the Sina Weibo microblog service, signed Gong Teng Xin Yi, said, "Congratulating Biden, the old friend of Chinese people on winning the election."
After Trump said he won "by a lot," the Communist Party newspaper People's Daily responded on Twitter, "HaHa."
President Tsai Ing-wen of Taiwan, the self-ruled island Beijing claims as part of its territory, expressed hope to "further our friendship." Biden had congratulated Tsai on her reelection in January, saying Taiwan is "stronger because of your free and open society." Washington has no formal relations with Taiwan, but Trump raised the profile of informal contacts by sending Cabinet officials to the island, an act that irritated Beijing.
There also was no immediate reaction from Russian President Vladimir Putin, who was friendly with Trump. Other leaders who supported Trump, including President Rodrigo Duterte of the Philippines, congratulated Biden, indicating they rejected Trump's claim the election wasn't over.
Most Western allies welcomed a fresh start with Washington. Many have been dismayed at Trump's criticism of decades-old military and economic alliances.
"We want to work in our cooperation for a new trans-Atlantic beginning, a New Deal," said German Foreign Minister Heiko Maas on Twitter.
Others expressed hope Biden might revive cooperation on health, climate and other issues following Trump's rejection of the proposed Trans-Pacific Partnership trade agreement and pressure on Canada, Mexico, South Korea and other partners to renegotiate trade terms.
"I look forward to working with President-elect Biden, Vice President-elect Harris, their administration, and the United States Congress as we tackle the world's greatest challenges together," Canadian Prime Minister Justin Trudeau, who was the target of personal insults by Trump, said on Twitter.
Prime Minister Scott Morrison of Australia told reporters he looked forward to a "great partnership" with Washington. He cited challenges including the coronavirus and "ensuring a free and open" Indo-Pacific region, a reference to China's disputes with its neighbors over control of vast tracts of ocean.
"American leadership is indispensable to meeting these challenges," Morrison said.
Prime Minister Imran Khan of Pakistan said he looked forward to working together to end illegal tax havens and on peacemaking in Afghanistan.
Other leaders who sent congratulations included German Chancellor Angela Merkel, French President Emmanuel Macron and Egyptian President Abdel-Fattah el-Sissi.
Embattled Venezuelan President Nicolas Maduro and his U.S.-backed rival, Juan Guaido, both congratulated Biden and Vice President-elect Kamala Harris. Maduro said Venezuela, which is under crippling U.S. sanctions aimed at forcing him out of office, was "ready for dialogue and understanding" with the United States.
The election outcome drew mixed reviews in Iraq, where Biden is remembered as a champion of the U.S. invasion in 2003. Still, Iraqi President Barham Salih described Biden as a friend and trusted partner.
In Iran, where the economy has been choked by U.S. sanctions, senior Vice President Eshaq Jahangiri wrote on Facebook, "The era of Trump and his warmongering and adventurist team is over." The newspaper Resalat published images of Trump without a mask against the coronavirus and Biden with a mask, and said, "Maskless enemy left, masked enemy arrived."
Congratulations also poured in from leaders who got along with Trump but ignored his claims the election wasn't over.
The Philippines' Duterte, who had said Filipino-Americans would "get the best deal with Trump," expressed hope for enhanced ties based on "shared commitment to democracy, freedom and the rule of law."
Crown Prince Mohammed bin Zayed Al Nahyan of the United Arab Emirates, who was close to Trump's son-in-law, Jared Kushner, extended his best wishes to Biden and Harris on Twitter.
Indian Prime Minister Narendra Modi, who has been known for public displays of bonhomie with Trump, shared a photo of himself with Biden and offered his congratulations "on your spectacular victory!"
British Prime Minister Boris Johnson, another Trump ally, said he looked forward to "working closely together on our shared priorities, from climate change to trade and security."
Harris's election inspired calls in parts of Africa for more women in government.
"The time has also come to give our women the chance to occupy such a high office in our country and even the number one position," said a Nigerian Cabinet minister, Festus Keyamo, on Twitter.
Others expressed hope Biden will help to heal divisions in American society and global politics.
"He seems open to accepting people's different viewpoints and wants to move forward in a united manner," said Mika Goto, a nursery school employee in Tokyo.
While outspoken disappointment was scarce, several prominent leaders who have maintained warm relations with Trump's administration kept silent.
That included President Jair Bolsonaro of Brazil and Crown Prince Mohammed bin Salman of Saudi Arabia. Mexican President Andres Manuel Lopez Obrador said he would wait "until all the issues are resolved."
Israeli Prime Minister Benjamin Netanyahu, whose Twitter profile photo shows him sitting beside Trump, described Biden as a friend of Israel and said he looked forward to working with him and Harris to "strength the special alliance" between their countries. In a separate statement, he thanked Trump for raising U.S.-Israeli relations to "unprecedented heights."
Many people, particularly in nations with turbulent politics, took Biden's win as improving the outlook for respect of democracy.
Among them was Tanzanian opposition leader Zitto Kabwe, who was arrested and charged with terrorism-related offenses after his country's bruising presidential election.
"This victory symbolizes the hope for democracy at a time when many other parts of the world are seeing that light diminishing," Kabwe said.
The outcome inspired disbelief in Slovenia, the homeland of first lady Melania Trump. Prime Minister Janez Jansa was the only leader who congratulated Trump even before all votes were counted and showed support after Biden's win was announced.