International donors have pledged $5.4bn (£3.4bn) for the Palestinians at a conference in Cairo.
The total, announced by the Norwegian Foreign Minister, Boerge Brende, exceeded the $4bn (£2.5bn) the Palestinian Authority had asked for.
Half the sum would be "dedicated" to work in Gaza, he said, without specifying a use for the other half.
At least 100,000 Gazans lost their homes in the 50-day conflict between Israel and Hamas earlier this year.
Much of the territory's infrastructure was damaged.
Earlier the Palestinian and Egyptian presidents called on Israel to commit to a long-term peace initiative.
Mahmoud Abbas and Abdul Fattah al-Sisi urged Israel to give up land seized in the 1967 Middle East war and accept a fair solution for Palestinian refugees in exchange for full recognition.
The seven-week Gaza conflict, which ended in a truce on 26 August, killed more than 2,100 Palestinians, most of them civilians, the UN says, along with 67 Israeli soldiers and six civilians in Israel.
Speaking at a news conference, Mr Brende said half of the $5.4bn promised would be dedicated to reconstruction, and the assistance would be distributed in response to the daily needs of Palestinians.
"This is a major breakthrough, a very important signal of solidarity to the Palestinian people in general and not at least to the people that are suffering so badly in Gaza," he said.
Envoys from dozens of countries attended the Cairo conference, which was hosted by Egypt's President Sisi.
Qatar alone promised $1bn (£622m).
The US pledged $212m (£132m) in new aid, while the United Arab Emirates and Turkey both committed $200m (£124m).
European Union foreign policy chief Catherine Ashton said donations from member states would reach $568m (£353m).
Cycle of conflict
Earlier US Secretary of State John Kerry said that with winter approaching, the thousands of Palestinians displaced from their homes needed urgent help.
"The people of Gaza do need our help desperately, not tomorrow, not next week, but they need it now" he said at the conference.
He added that anything other than a long-term commitment to peace would be a "band-aid fix".
At the opening of the conference, President Sisi urged "the Israelis, both the people and the government" to put an end to the conflict.
"We should turn this moment into a real starting point to achieve a peace that secures stability and flourishing and renders the dream of coexistence a reality," he said.
Correspondents say some neighbourhoods in Gaza resembled earthquake zones following intense bombardment from Israel during the war. The Israeli air strikes had sought to halt rocket-fire from Gaza.
The two sides have fought three wars in six years.
Israel was not invited to the conference but Foreign Minister Avigdor Lieberman earlier said any rebuilding efforts would need his government's consent.
"You can't reconstruct Gaza without Israeli participation and without Israeli co-operation," he told news website Ynet ahead of the meeting on Sunday.
"In any case, we will try to be positive about the civil infrastructure and the rehabilitation of civilians."
Rebuilding depends on Israel allowing in enough construction materials, the BBC's Orla Guerin in Cairo reports.
This is a contentious issue because Hamas has used cement to build tunnels into Israeli territory in the past, our correspondent adds.
Hour of need
Announcing the UK's $32m donation in Cairo, International Development Minister Desmond Swayne said the international community could not continue to pick up the pieces of the conflict indefinitely.
"It is critical that reconstruction efforts now form part of a process of meaningful political change," he said.
The Gaza Strip, sandwiched between Israel and Egypt, has been a recurring flashpoint in the Israel-Palestinian conflict for years.
Israel occupied Gaza in the 1967 Middle East war and pulled its troops and settlers out in 2005.
Israel considered this the end of the occupation, though the UN continues to regard Gaza as part of Israeli-occupied Palestinian territory.
Israel exercises control over most of Gaza's borders, waters and airspace, while Egypt controls Gaza's southern border.